diff --git a/package.json b/package.json
index a7b05719..2adafe4b 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "dm-manager",
-  "version": "1.3.12",
+  "version": "1.3.13",
   "private": true,
   "dependencies": {
     "@fortawesome/fontawesome-svg-core": "^6.1.2",
diff --git a/server/controllers/Controller.js b/server/controllers/Controller.js
index 1407345e..551628bd 100644
--- a/server/controllers/Controller.js
+++ b/server/controllers/Controller.js
@@ -1,4 +1,6 @@
 const { ObjectId } = require('mongoose').Types
+
+const User = require('../models/User')
 const {log, requireSomeRole, requireUser, allowAnonymous} = require('./middleware') 
 
 function sendBadRequest(res, message) {
@@ -541,6 +543,12 @@ class Controller {
         try {
             const was = await this.Model.findById(id)
             await log(req, was, payload)
+            if (was.createdBy !== undefined) delete payload.createdBy
+            if (payload.createdBy) {
+                const user = await User.findOne({username: payload.createdBy})
+                if (!user) throw new Error(`user ${payload.createdBy} not found`)
+                payload.createdBy = user._id
+            }
             was.set({...was, ...payload})
             await was.save()
             res.send(was)
@@ -612,7 +620,8 @@ class Controller {
                     const payload = {...req.body,
                         updatedBy: req.user._id
                     }
-                    delete payload.createdBy
+                    // è possibile modificare l'owner se undefined
+                    //delete payload.createdBy
                     delete payload.createdAt
                     delete payload.updatedAt
                     this.patch(req, res, req.params.id, payload)
diff --git a/src/components/ModelEdit.js b/src/components/ModelEdit.js
index 35d20ec4..9fad043e 100644
--- a/src/components/ModelEdit.js
+++ b/src/components/ModelEdit.js
@@ -3,7 +3,7 @@ import { Form, Button, ButtonGroup } from 'react-bootstrap'
 import { Card } from 'react-bootstrap'
 
 import { useEngine } from '../Engine'
-import { ModelInputs } from '../components/ModelInput'
+import { ModelInput, ModelInputs } from '../components/ModelInput'
 import Timestamps from '../components/Timestamps'
 import Loading from '../components/Loading'
 
@@ -56,8 +56,9 @@ export default function ModelEdit({Model, id, clone_id, onSave, onCancel, onDele
         return v1 === v2
     }
 
-    const modifiedFields = Object.keys(modifiedObj)
+    const modifiedFields = [...Object.keys(modifiedObj)]
         .filter(key => !compareValue(modifiedObj[key], originalObj[key]))
+    console.log(`Modified fields: ${JSON.stringify(modifiedFields)}`)
 
     const changed = modifiedFields.length > 0
 
@@ -105,6 +106,22 @@ export default function ModelEdit({Model, id, clone_id, onSave, onCancel, onDele
                 modifiedFields={modifiedFields}
                 onChange={onChange && onChange(setModifiedObj)} 
                 />
+            { /* input speciale per modificare il campo createdBy */
+                originalObj.createdBy === undefined && !create && 
+                <ModelInput 
+                    schema={{
+                        label: 'Creato da',
+                        ...Model.schema.fields.createdBy}} 
+                    setValue={(value) => {
+                            setModifiedObj(obj => ({...obj, createdBy: value}))
+                        }}
+                    edit={true}
+                    value={modifiedObj.createdBy}
+                    obj={modifiedObj} 
+                    setObj={setModifiedObj} 
+                    modified={modifiedFields.includes("createdBy")}
+                    onChange={onChange && onChange(setModifiedObj)} 
+            />}
             <ButtonGroup className="mt-3">
                 <Button 
                     onClick={ submit } 
@@ -121,12 +138,12 @@ export default function ModelEdit({Model, id, clone_id, onSave, onCancel, onDele
                     onClick={ () => deleteObj(modifiedObj) }
                     className="btn btn-danger pull-right">
                         elimina {objName}
-                </Button>}
+                </Button>}  
             </ButtonGroup>
           </Form>
         </Card.Body>
         <Card.Footer>
-            <Timestamps obj={originalObj} />
+            <Timestamps obj={originalObj}/>
         </Card.Footer>
     </Card>
 }
diff --git a/src/components/ModelInput.js b/src/components/ModelInput.js
index 59c759ee..24d15b55 100644
--- a/src/components/ModelInput.js
+++ b/src/components/ModelInput.js
@@ -53,12 +53,14 @@ export function ModelFieldInput({ id, schema, value, setValue, api_prefix }) {
         if (schema.items['x-ref'] === 'Institution') return element(InstitutionInput, {multiple:true, api_prefix: api_prefix})
         return <p>x-ref to {schema.items['x-ref']} not yet implemented in array</p>
     } else {
-        if (schema['x-ref'] === 'Person') return element(PersonInput, {api_prefix: api_prefix})
-        if (schema['x-ref'] === 'Room') return element(RoomInput, {api_prefix: api_prefix})
-        if (schema['x-ref'] === 'ConferenceRoom') return element(ConferenceRoomInput, {api_prefix: api_prefix})
-        if (schema['x-ref'] === 'SeminarCategory') return element(SeminarCategoryInput, {api_prefix: api_prefix})
-        if (schema['x-ref'] === 'Institution') return element(InstitutionInput, {api_prefix: api_prefix})
-        if (schema['x-ref']) return <p>x-ref to {schema['x-ref']} not yet implemented</p> 
+        const xref = schema['x-ref']
+        if (xref === 'Person') return element(PersonInput, {api_prefix: api_prefix})
+        if (xref === 'Room') return element(RoomInput, {api_prefix: api_prefix})
+        if (xref === 'ConferenceRoom') return element(ConferenceRoomInput, {api_prefix: api_prefix})
+        if (xref === 'SeminarCategory') return element(SeminarCategoryInput, {api_prefix: api_prefix})
+        if (xref === 'Institution') return element(InstitutionInput, {api_prefix: api_prefix})
+        if (xref === 'User') return element(StringInput, {api_prefix: api_prefix})
+        if (xref) return <p>x-ref to {xref} not yet implemented</p> 
         if (schema.format === 'date-time') {
             if (schema.widget === 'datetime') return element(DatetimeInput) // use formatted text input "YYYY-MM-DD HH:mm"
             return element(DateInput) // use date only widget
@@ -84,7 +86,7 @@ export function ModelFieldInput({ id, schema, value, setValue, api_prefix }) {
 
 export function ModelInput({ field, modified, schema, value, setValue, api_prefix}) {
     const id = useId()
-    const label = schema.items?.label || schema.label || field
+    const label = schema?.items?.label || schema?.label || field
 
     return <Form.Group className="row my-2">
         <Form.Label className={ "col-form-label text-end col-sm-2 " + (modified ? "bg-warning" : "") } htmlFor={ id }>
@@ -100,7 +102,7 @@ export function ModelInput({ field, modified, schema, value, setValue, api_prefi
             />                         
         </div>
         <div className="col-sm-2"></div>
-        <div className="col-sm-10 form-text">{schema.help}</div>
+        <div className="col-sm-10 form-text">{schema?.help}</div>
     </Form.Group>
 }