diff --git a/src/04-modality-specific-files/01-magnetic-resonance-imaging-data.md b/src/04-modality-specific-files/01-magnetic-resonance-imaging-data.md
index f52e2b38ea..64affdf314 100644
--- a/src/04-modality-specific-files/01-magnetic-resonance-imaging-data.md
+++ b/src/04-modality-specific-files/01-magnetic-resonance-imaging-data.md
@@ -135,7 +135,7 @@ Anatomical (structural) data acquired for that participant. Currently supported
 modalities include:
 
 | **Name**           | `modality_label` | **Description**                                                                                                                                   |
-| ------------------ | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- |
+|--------------------|------------------|---------------------------------------------------------------------------------------------------------------------------------------------------|
 | T1 weighted        | T1w              |                                                                                                                                                   |
 | T2 weighted        | T2w              |                                                                                                                                                   |
 | T1 Rho map         | T1rho            | Quantitative T1rho brain imaging <br> <https://www.ncbi.nlm.nih.gov/pubmed/24474423> <br> <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4346383/> |
@@ -565,6 +565,163 @@ JSON example:
 }
 ```
 
+## Arterial Spin Labeling perfusion data
+
+Template:
+
+```Text
+sub-<label>/[ses-<label>/]
+    perf/
+       sub-<label>[_ses-<label>][_acq-<label>][_rec-<label>][_dir-<label>][_run-<index>]_asl.nii[.gz]
+       sub-<label>[_ses-<label>][_acq-<label>][_rec-<label>][_dir-<label>][_run-<index>]_asl.json
+       sub-<label>[_ses-<label>][_acq-<label>][_rec-<label>][_dir-<label>][_run-<index>]_aslcontext.tsv
+       sub-<label>[_ses-<label>][_acq-<label>][_rec-<label>][_dir-<label>][_run-<index>]_m0scan.nii[.gz]
+       sub-<label>[_ses-<label>][_acq-<label>][_rec-<label>][_dir-<label>][_run-<index>]_m0scan.json
+       sub-<label>[_ses-<label>][_acq-<label>][_rec-<label>][_run-<index>]_labeling.jpg
+```
+
+The complete ASL time series should be stored as a 4D NIfTI file in the original acquisition order, accompanied by two ancillary 
+files: `*_asl.json` and `*_aslcontext.tsv`. The `*_asl.nii.gz` and `*_m0scan.nii.gz` should contain appropriately scaled data and no scaling factors 
+should be stored in the ancillary files or in the NIfTI header. 
+
+The `m0scan` can either be stored inside the 4D ASL time-series NIfTI file or as a separate NIfTI file, depending on whether it 
+was acquired within the ASL time-series or as a separate scan. These and other M0 options are specified in the required `M0` field of the `*_asl.json` file. 
+It can also be stored under `fmap/sub-<label>[_ses-<label>][_acq-<label>][_ce-<label>]_dir-<label>[_run-<index>]_m0scan.nii[.gz]`, 
+when the pepolar approach is used.
+
+### `*_aslcontext.tsv`
+The `*_aslcontext.tsv` lists the volume_type for each volume in a single column, in the `*_asl.nii[.gz]`, corresponding to the volume_types specified in the table below, based 
+on DICOM Tag (0018,9257) `ASL Context`. Note that the volume_types `control` and  `label` within BIDS do not discriminate between types of labeling, but only serve to specify 
+the magnetization state of the blood and thus the ASL subtraction order.
+
+| **volume_type** | **Definition**                                                                                                                                                                         |
+|-----------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| control         | The control image is acquired in the exact same way as the label image, except that the magnetization of the blood flowing into the imaging region has not been inverted.              |
+| label           | The label image is acquired in the exact same way as the control image, except that the blood magnetization flowing into the imaging region has been inverted.                         |
+| m0scan          | The M0 image is a calibration image, used to estimate the equilibrium magnetization of blood.                                                                                          |
+| deltam          | The deltaM image is a perfusion-weighted image, obtained by the subtraction of `control` - `label`.                                                                                    |
+| cbf             | The cerebral blood flow (CBF) image is produced by dividing the deltaM by the M0, quantified into `mL/100g/min` (See also [doi:10.1002/mrm.25197](https://doi.org/10.1002/mrm.25197)). |
+
+If the `control` and `label` images are not available, their derivative `deltam` should be stored within the `*_asl.nii[.gz]` and specified in the `*_aslcontext.tsv` instead. If 
+the `deltam` is not available, `cbf` should be stored within the `*_asl.nii[.gz]` and specified in the `*_aslcontext.tsv`. When `cbf` is stored within the `*_asl.nii[.gz]`, its 
+units need to be specified in the `*_asl.json` as well. See below examples of these cases, in order of decreasing preference.
+
+#### Case 1: `*_asl.nii[.gz]` consists of volume_types `control`, `label`
+
+In most cases, the ASL timeseries, provided by the scanner, consist of a series of `control` and `label`, and optionally `m0scan`, volumes. In this case, only the `control`, 
+`label`, and optionally `m0scan` volumes should be stored in the `*_asl.json`, and the exact volume_type series should be specified in the `*_aslcontext.tsv`. The optional 
+`deltam` or `cbf` volumes should be stored and specified as derivative. Example of `*_aslcontext.tsv`:
+
+| volume_type |
+|-------------|
+| control     |
+| label       |
+| control     |
+| label       |
+| [m0scan]    |
+
+#### Case 2: `*_asl.nii[.gz]` consists of volume_types `deltam` (scanner does not export `control` or `label` volumes)
+
+In some cases, `control` and `label` volumes are lacking within the acquired ASL timeseries, but the intermediate `deltam` - and optionally a `m0scan` - volume is 
+reconstructed/exported by the scanner. In this case, the `deltam` should be included in the `*_asl.nii[.gz]` and specified in the `*_aslcontext.tsv`. An optional `cbf` volume 
+should be stored and specified as derivative. Example of `*_aslcontext.tsv`:
+
+| volume_type |
+|-------------|
+| deltam      |
+| [m0scan]    |
+
+#### Case 3: `*_asl.nii[.gz]` consists of volume_type `cbf` (scanner does not export `control`, `label`, or `deltaM` volumes) 
+
+If `control` and `label` or intermediate ASL volumes are not reconstructed or exported, but a pre-calculated `cbf` - and optionally a `m0scan` - volume is provided by the
+scanner, the `cbf` should be included in the `*_asl.nii[.gz]` and specified in the `*_aslcontext.tsv`. Example of `*_aslcontext.tsv`:
+
+| volume_type |
+|-------------|
+| cbf         |
+| [m0scan]    |
+
+### `*_asl.json` file
+
+Depending on the method used for ASL acquisition (i.e. (P)CASL or PASL) different metadata fields are applicable.
+
+#### Common metadata fields applicable to both (P)CASL and PASL 
+| **Key name**                      | **Requirement level**                                                                                                           | **Data type**                           | **Description**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
+|-----------------------------------|---------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| LabelingType                      | REQUIRED                                                                                                                        | [string][]                              | `CASL` , `PCASL` , `PASL`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
+| PostLabelingDelay                 | REQUIRED                                                                                                                        | [number][] or [array][] of [numbers][]  | This is the postlabeling delay (PLD) time, in seconds, after the end of the labeling (for `(P)CASL`) or middle of the labeling pulse (for `PASL`) until the middle of the excitation pulse applied to the imaging slab (for 3D acquisition) or first slice (for 2D acquisition).  Can be a number (for a single-PLD time series) or an array of numbers (for multi-PLD and Look-Locker). In the latter case, the array of numbers contains the PLD of each volume, namely each `control` and `label`, in the acquisition order. Any image within the time-series without a PLD, for example an `m0scan`, is indicated by a zero. Based on DICOM Tags 0018,9079 `Inversion Times` and 0018,0082 `InversionTime`.                                                                                                                                                                                                                                                                                                                                                                                                          |
+| BackgroundSuppression             | REQUIRED                                                                                                                        | [boolean][]                             | Boolean indicating if background suppression is used.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
+| M0                                | REQUIRED                                                                                                                        | [number][] or [string][] or [boolean][] | Describes the available M0 information or the location of an `m0scan` file, as either: *Numerical*: a single numerical whole-brain M0 value, for example obtained from CSF in another sequence; *SeparateFile*: `*_m0scan.nii[.gz]`; *Within ASL time-series*: *Boolean: `true`* referring to an `m0scan` within the time-series (as defined within the `*_aslcontext.tsv`); *`false`* referring to the use of the (average) `control` image for M0 calibration.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+| MagneticFieldStrength             | REQUIRED                                                                                                                        | [number][]                              | Nominal field strength of MR magnet in Tesla. Corresponds to DICOM Tag 0018,0087 `Magnetic Field Strength`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
+| PulseSequenceType                 | REQUIRED                                                                                                                        | [string][]                              | General description of the pulse sequence used for the scan. Allowed values are any combination of 2D or 3D acquisition, with the read-out type, separated by an underscore: for example “2D_EPI”, “3D_GRASE”, “3D_spiral”.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
+| EchoTime                          | REQUIRED                                                                                                                        | [number][] or [array][] of [numbers][]  | The echo time for the acquisition, specified in seconds. Specify either one number for the total time-series, or provide an array of numbers with different values of each volume. Corresponds to DICOM Tag 0018, 0081 `Echo Time` (please note that the DICOM term is in milliseconds not seconds).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
+| SliceTiming                       | RECOMMENDED, but REQUIRED in case of a 2D acquisition, or when `VolumeTiming` is defined                                          | [array][] of [numbers][]                | The time at which each slice was acquired within each volume (frame) of the acquisition with respect to the beginning of volume acquisition, namely after the `PostLabelingDelay`. In the case of 3D acquisition, a zero is entered. The length of this array of numbers should be equal to the number of slices for 2D acquisition, with the first time being zero, effectively equal to the `PostLabelingDelay`. Slice timing is not the same as slice order. Rather, it is a list of times containing the time (in seconds) of each slice acquisition in relation to the beginning of volume acquisition. The list goes through the slices along the slice axis in the slice encoding dimension. Note that to ensure the proper interpretation of the `SliceTiming` field, it is important to check if the OPTIONAL `SliceEncodingDirection` exists. In particular, if `SliceEncodingDirection` is negative, the entries in `SliceTiming` are defined in reverse order with respect to the slice axis, such that the final entry in the `SliceTiming` list is the time of acquisition of slice zero. |
+| RepetitionTime                    | REQUIRED, mutually exclusive with `VolumeTiming`                                                                                | [number][]                              | The time in seconds between the acquisition start of one volume and the acquisition start of the subsequent volume, including any deadtime. `RepetitionTime` is specified when all volumes in a series/NIfTI have the same time between acquired volumes. Otherwise, use the `VolumeTiming` field instead. This field is derived from DICOM Tag 0018, 0080.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
+| VolumeTiming                      | REQUIRED, mutually exclusive with `RepetitionTime`                                                                              | [array][] of [numbers][]                | The time at which each volume was acquired during the acquisition, referring to the start of each readout in the ASL time series. Use this field instead of the `RepetitionTime` field in the case that the ASL time series have a non-uniform time distance between acquired volumes. The list must have the same length as the `*_aslcontext.tsv`, and the numbers must be non-negative and monotonically increasing. If `VolumeTiming` is defined, this requires acquisition time (TA) to be defined via `AcquisitionDuration`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+| VascularCrushing                  | RECOMMENDED                                                                                                                     | [boolean][]                             | Boolean indicating if Vascular Crushing is used. Corresponds to DICOM Tag 0018,9259 `ASL Crusher Flag`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
+| AcquisitionVoxelSize              | RECOMMENDED                                                                                                                     | [array][] of [numbers][]                | An array of numbers with a length of 3, in millimeters. This parameter denotes the original acquisition voxel size, excluding any inter-slice gaps and before any interpolation or resampling within reconstruction or image processing. Any point spread function effects, for example due to T2-blurring, that would decrease the effective resolution are not considered here.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
+| FlipAngle                         | RECOMMENDED, REQUIRED for ASL-sequences that use a Look-Locker readout and/or multiple flip angles (for example (turbo-)QUASAR) | [number][] or [array][] of [numbers][]  | Flip angle for the acquisition, specified in degrees, either as a number or an array of numbers, with the length corresponding to the number of volumes. Corresponds to: DICOM Tag 0018, 1314 `Flip Angle`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
+| TotalAcquiredVolumes              | OPTIONAL, but RECOMMENDED when not all 3D volumes are provided by the scanner                                                   | [array][] of [numbers][]                | The original number of 3D volumes acquired for each volume defined in the `*_aslcontext.tsv`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
+| BackgroundSuppressionNumberPulses | OPTIONAL, RECOMMENDED if `BackgroundSuppression` is `true`                                                                      | [number][]                              | The number of background suppression pulses used. Note that this excludes any effect of background suppression pulses applied before the labeling.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
+| BackgroundSuppressionPulseTime    | OPTIONAL, RECOMMENDED if `BackgroundSuppression` is `true`                                                                      | [array][] of [numbers][]                | Array of numbers containing timing, in seconds, of the background suppression pulses before the start of the readout. In case of multi-PLD with different background suppression pulse times, only the pulse time of the first PLD should be defined.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
+| VascularCrushingVENC              | OPTIONAL, RECOMMENDED if `VascularCrushing` is `true`                                                                           | [number][] or [array][] of [numbers][]  | The crusher gradient strength, in centimeters per second. Specify either one number for the total time-series, or provide an array of numbers, for example when using QUASAR, using the value zero to identify volumes for which `VascularCrushing` was turned off. Corresponds to DICOM Tag 0018,925A `ASL Crusher Flow Limit`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+| LabelingOrientation               | RECOMMENDED                                                                                                                     | [array][] of [numbers][]                | Orientation of the labeling plane (`(P)CASL`) or slab (`PASL`). The direction cosines of a normal vector perpendicular to the ASL labeling slab or plane with respect to the patient. Corresponds to DICOM Tag 0018,9255 `ASL Slab Orientation`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+| LabelingDistance                  | RECOMMENDED                                                                                                                     | [number][]                              | Distance from the center of the imaging slab to the center of the labeling plane (`(P)CASL`) or the leading edge of the labeling slab (`PASL`), in millimeters. If the labeling is performed inferior to the isocenter, this number should be negative. Based on DICOM macro C.8.13.5.14.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
+| LabelingLocationDescription       | RECOMMENDED                                                                                                                     | [string][]                              | Description of the location of the labeling plane (`(P)CASL`) or the labeling slab (`PASL`) that cannot be captured by fields ‘LabelingOrientation’ or ‘LabelingDistance’. May include a link to an anonymized screenshot of the planning of the labeling slab/plane with respect to the imaging slab or slices `*_labeling.jpg`. Based on DICOM macro C.8.13.5.14.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
+| LookLocker                        | OPTIONAL                                                                                                                        | [boolean][]                             | Boolean indicating if a Look-Locker readout is used.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
+| LabelingEfficiency                | OPTIONAL                                                                                                                        | [number][]                              | Labeling efficiency, specified as a number between zero and one, only if obtained externally (for example phase-contrast based).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
+
+#### (P)CASL-specific metadata fields
+These fields can only be used when `LabelingType` is `CASL` or `PCASL`.
+
+| **Key name**                 | **Requirement level** | **Data type**                          | **Description**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
+|------------------------------|-----------------------|----------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| LabelingDuration             | REQUIRED              | [number][] or [array][] of [numbers][] | Total duration of the labeling pulse train, in seconds, corresponding to the temporal width of the labeling bolus for `(P)CASL`. Specify either one number for total time-series or provide an array of numbers of different values for each volume in case of sequential acquisitions with varying labeling duration. In the case that an array of numbers is provided, its length should be equal to the number of volumes specified in `*_aslcontext.tsv`. An `m0scan` acquired within the ASL time-series, gets a value of zero. Corresponds to DICOM Tag 0018,9258 `ASL Pulse Train Duration`. |
+| PCASLType                    | RECOMMENDED           | [string][]                             | Type the gradient pulses used in the `control` condition: `balanced` or `unbalanced`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
+| CASLType                     | RECOMMENDED           | [string][]                             | Describes if a separate coil is used for labeling: `single-coil` or `double-coil`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
+| LabelingPulseAverageGradient | RECOMMENDED           | [number][]                             | The average labeling gradient, in milliteslas per meter.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
+| LabelingPulseMaximumGradient | RECOMMENDED           | [number][]                             | The maximum amplitude of the gradient switched on during the application of the labeling RF pulse(s), in milliteslas per meter.                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
+| LabelingPulseAverageB1       | RECOMMENDED           | [number][]                             | The average B1-field strength of the RF labeling pulses, in microteslas. As an alternative, `LabelingPulseFlipAngle` can be provided.                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
+| LabelingPulseDuration        | RECOMMENDED           | [number][]                             | Duration of the individual labeling pulses, in seconds.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
+| LabelingPulseFlipAngle       | RECOMMENDED           | [number][]                             | The flip angle of a single labeling pulse, in degrees, which can be given as an alternative to `LabelingPulseAverageB1`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
+| LabelingPulseInterval        | RECOMMENDED           | [number][]                             | Delay between the peaks of the individual labeling pulses, in seconds.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
+
+#### PASL-specific metadata fields
+These fields can only be used when `LabelingType` is `PASL`.
+
+| **Key name**          | **Requirement level**                             | **Data type**                          | **Description**                                                                                                                                                                                                                                                                                                                                                                                                                                         |
+|-----------------------|---------------------------------------------------|----------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| BolusCutOffFlag       | REQUIRED                                          | [boolean][]                            | Boolean indicating if a bolus cut-off technique is used. Corresponds to DICOM Tag 0018,925C `ASL Bolus Cut-off Flag`.                                                                                                                                                                                                                                                                                                                                   |
+| PASLType              | RECOMMENDED                                       | [string][]                             | Type of the labeling pulse of the `PASL` labeling, for example FAIR, EPISTAR, or PICORE.                                                                                                                                                                                                                                                                                                                                                                |
+| LabelingSlabThickness | RECOMMENDED                                       | [number][]                             | Thickness of the labeling slab in millimeters. For non-selective FAIR a zero is entered. Corresponds to DICOM Tag 0018,9254 `ASL Slab Thickness`.                                                                                                                                                                                                                                                                                                       |
+| BolusCutOffDelayTime  | OPTIONAL, REQUIRED if `BolusCutOffFlag` is `true` | [number][] or [array][] of [numbers][] | Duration between the end of the labeling and the start of the bolus cut-off saturation pulse(s), in seconds. This can be a number or array of numbers, of which the values must be non-negative and monotonically increasing, depending on the number of bolus cut-off saturation pulses. For Q2TIPS, only the values for the first and last bolus cut-off saturation pulses are provided. Based on DICOM Tag 0018,925F `ASL Bolus Cut-off Delay Time`. |
+| BolusCutOffTechnique  | OPTIONAL, REQUIRED if `BolusCutOffFlag` is `true` | [string][]                             | Name of the technique used, for example Q2TIPS, QUIPSS, QUIPSSII. Corresponds to DICOM Tag 0018,925E `ASL Bolus Cut-off Technique`.                                                                                                                                                                                                                                                                                                                     |
+
+### `m0scan` metadata fields
+| **Key name**         | **Requirement level** | **Data type**                          | **Description**                                                                                                                                                                                                                                                                                                                                                                   |
+|----------------------|-----------------------|----------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| IntendedFor          | REQUIRED              | [string][] or [array][] of [strings][] | One or more filenames with paths relative to the subject subfolder, with forward slashes, referring to ASL time series for which the m0scan is intended.                                                                                                                                                                                                                           |
+| AcquisitionVoxelSize | RECOMMENDED           | [array][] of [numbers][]               | An array of numbers with a length of 3, in millimeters. This parameter denotes the original acquisition voxel size, excluding any inter-slice gaps and before any interpolation or resampling within reconstruction or image processing. Any point spread function effects, for example due to T2-blurring, that would decrease the effective resolution are not considered here. |
+
+The following table recapitulates the ASL field dependencies. If Source field (column 1) contains the Value specified in column 2, then the Requirements in column 4 are imposed on the Dependent fields in column 3.
+
+| **Source field**              | **Value**                       | **Dependent field**           | **Requirements**              |
+|-------------------------------|---------------------------------|-------------------------------|-------------------------------|
+| PulseSequenceType             | 2D acquisition / 3D acquisition | SliceTiming                   | \[X\] / \[\]                  |
+| LookLocker                    | true                            | FlipAngle                     | \[X\]                         |
+| M0                            | true / false                    | `*_aslcontext.tsv`            | Contains `m0scan` / `control` |
+| LabelingType                  | PASL                            | BolusCutOffFlag               | \[X\]                         |
+| BolusCutOffFlag               | true / false                    | BolusCutOffDelayTime          | \[X\] / \[\]                  |
+| BolusCutOffFlag               | true / false                    | BolusCutOffTechnique          | \[X\] / \[\]                  |
+| `*_aslcontext.tsv`            | cbf                             | Units                         | \[X\]                         |
+| RepetitionTime / VolumeTiming | \[X\] / \[\]                    | VolumeTiming / RepetitionTime | \[\] / \[X\]                  |
+| VolumeTiming                  | \[X\]                           | AcquisitionDuration           | \[X\]                         |
+
+**Legend**
+
+-   \[ X ] --> MUST be defined
+-   \[   \] --> MUST NOT be defined
+
 ## Fieldmap data
 
 Data acquired to correct for *B<sub>0</sub>* inhomogeneities can come in different forms.
@@ -704,7 +861,7 @@ for details on the `IntendedFor` field.
 The phase-encoding polarity (PEpolar) technique combines two or more Spin Echo
 EPI scans with different phase encoding directions to estimate the distortion
 map corresponding to the nonuniformities of the *B<sub>0</sub>* field.
-These `_epi.nii[.gz]` files can be 3D or 4D --
+These `_epi.nii[.gz]` - or _m0scan.nii[.gz] for arterial spin labeling perfusion data - files can be 3D or 4D --
 in the latter case, all timepoints share the same scanning parameters.
 Examples of software tools using these kinds of images are FSL TOPUP,
 AFNI `3dqwarp`, and SPM.
@@ -716,6 +873,8 @@ sub-<label>/[ses-<label>/]
     fmap/
         sub-<label>[_ses-<label>][_acq-<label>][_ce-<label>]_dir-<label>[_run-<index>]_epi.nii[.gz]
         sub-<label>[_ses-<label>][_acq-<label>][_ce-<label>]_dir-<label>[_run-<index>]_epi.json
+        sub-<label>[_ses-<label>][_acq-<label>][_ce-<label>]_dir-<label>[_run-<index>]_m0scan.nii[.gz]
+        sub-<label>[_ses-<label>][_acq-<label>][_ce-<label>]_dir-<label>[_run-<index>]_m0scan.json
 ```
 
 The [`dir-<label>`](../99-appendices/09-entities.md#dir) entity is REQUIRED
diff --git a/src/99-appendices/01-contributors.md b/src/99-appendices/01-contributors.md
index a4bc900cc8..55ef7e329c 100644
--- a/src/99-appendices/01-contributors.md
+++ b/src/99-appendices/01-contributors.md
@@ -36,7 +36,10 @@ The following individuals have contributed to the Brain Imaging Data Structure
 ecosystem (in alphabetical order).
 If you contributed to the BIDS ecosystem and your name is not listed, please add it.
 
+-   Eric Achten 📖🔣📓
+-   Azeez Adebimpe 📖
 -   Fidel Alfaro Almagro 💬📖💡🔌
+-   David Alsop 📖
 -   Stefan Appelhoff 📖💬🤔🐛💡💻👀⚠️📢✅🔧🔌📝🚧🔣
 -   Tibor Auer 💬📖💡🔧📢
 -   Sylvain Baillet 📖🔍
@@ -48,8 +51,12 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Teon L. Brooks 📖💻⚠️💬👀🤔🔧🐛📢
 -   Suyash Bhogawar 📖💡⚠️🔧💬
 -   Vince D. Calhoun 📖
+-   Marco Castellaro 💬🐛💻📖💡⚠️📢🚇
+-   Michael Chappell 📖🔣📆
+-   Patricia Clement 💬🐛💻📖🔣💡📋🤔📆⚠️📢
 -   Alexander L. Cohen 🐛💻📖💬
 -   R. Cameron Craddock 📖📢
+-   Martin Craig 🔣
 -   Sasha D'Ambrosio 📖
 -   Samir Das 📖
 -   Olivier David 📖
@@ -67,6 +74,7 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Guillaume Flandin 📖💻
 -   Adeen Flinker 📖
 -   Brett L. Foster 📖
+-   Ana Fouto 📓
 -   Remi Gau 📖💻💬📢🐛💻🚇👀🔧🤔
 -   Satrajit S. Ghosh 📖💻
 -   Tristan Glatard 📖💻
@@ -77,27 +85,34 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Iris Groen 📖
 -   David Groppe 📖
 -   Aysegul Gunduz 📖
+-   Matthias Günther 📖
 -   Yaroslav O. Halchenko 📖📢🔧💬🐛
 -   Liberty Hamilton 📖
+-   Tom Hampshire 📖
 -   Daniel A. Handwerker 📖
 -   Michael Hanke 📖🤔🔧🐛📢
 -   Michael P. Harms 📖⚠️🔧
 -   Richard N. Henson 📖
 -   Peer Herholz 💬📖👀🔧✅📢
 -   Dora Hermes 📖💻✅🔍🤔
+-   Luis Hernandez-Garcia 📖📓
 -   Katja Heuer 🔧
 -   Richard Höchenberger 📖
 -   Chris Holdgraf 📖🤔
 -   Christopher J. Honey 📖
 -   Jean-Christophe Houde 📖
 -   International Neuroinformatics Coordinating Facility 💵📋
+-   Andrew Jahn 📓
 -   Andrew Janke 📖💻
 -   Mainak Jas 📖💻
 -   Alexander Jones 💻🐛
+-   Tamás Józsa 📓
 -   David Keator 📖
 -   James Kent 💬💻
 -   Gregory Kiar 📖💻🎨🔧
+-   Thomas Kirk 📖
 -   Robert Knight 📖
+-   Joost Kuijer 📖
 -   Jean-Philippe Lachaux 📖
 -   Marc Lalancette 📖
 -   Pamela LaMontagne 📖💡
@@ -118,7 +133,7 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Zachary Michael 📖
 -   Ezequiel Mikulan 📖💻
 -   Michael P. Milham 💡🔍
--   Henk Mutsaerts 📖
+-   Henk Mutsaerts 💬🐛💻📖💡📋🤔📆📢📓
 -   National Institute of Mental Health 💵
 -   Mikael Naveau 🐛
 -   B. Nolan Nichols 📖
@@ -127,13 +142,17 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Guiomar Niso 📖💡📢
 -   Michael P. Notter 💬📝✅📢📖
 -   Jeffrey G. Ojemann 📖
+-   Thomas Okell 📖
+-   Aaron Oliver-Taylor 📖
 -   Robert Oostenveld 📖🔧📢💡✅⚠️🤔
 -   Dimitri Papadopoulos Orfanos 📖💡🤔💬
 -   Patrick Park 📖💡💬
+-   Maurice Pasternak 📓
 -   Dianne Patterson 📖
 -   John Pellman 📖
 -   Cyril Pernet 💬📝📖🎨💡📋🤔📢
 -   Franco Pestilli 📖💻🎨💡🤔👀🔧
+-   Jan Petr 💬🐛💻📖🔣💡📋🤔📆⚠️📢
 -   Natalia Petridou 📖
 -   Dmitry Petrov 📖💻
 -   Christophe Phillips 📖
@@ -149,6 +168,7 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Kay Robbins 💻📖🐛
 -   Alex Rockhill 📖🔧
 -   Ariel Rokem 📖
+-   Chris Rorden 📖💻
 -   Taylor Salo 💬📖🔌
 -   Matt Sanderson 📖💻
 -   Gunnar Schaefer 📖
@@ -158,11 +178,14 @@ If you contributed to the BIDS ecosystem and your name is not listed, please add
 -   Arjen Stolk 📖
 -   Nicole C. Swann 📖
 -   François Tadel 📖🔌💡
+-   David Thomas 📖🔣
 -   Roberto Toro 🔧
 -   Sébastien Tourbier 🤔👀📢🐛💻📖
 -   William Triplett 📖
 -   Jessica A. Turner 📖
+-   Pieter Vandemaele 📖💻
 -   Max A. van den Boom 💻👀📖
+-   Matthias Van Osch 📖
 -   Bradley Voytek 📖
 -   Brian A. Wandell 📖
 -   Joseph Wexler 📖💡