diff --git a/README.md b/README.md
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+++ b/README.md
@@ -102,6 +102,6 @@ Once the command above finishes, you will see the following output files:
 
 ## How to cite
 
-Dating the bacterial tree of life based on ancient symbiosis Sishuo Wang, Haiwei Luo bioRxiv 2023.06.18.545440; doi: <https://doi.org/10.1101/2023.06.18.545440>.
+Dating the bacterial tree of life based on ancient symbiosis Sishuo Wang, Haiwei Luo bioRxiv 2023.06.18.545440; doi: https://doi.org/10.1101/2023.06.18.545440.
 
 You may also need to cite corresponding papers for the use of `PAML`, `IQ-TREE`, and `Newick Utilities`.