diff --git a/doc/requirements.txt b/doc/requirements.txt
index 155a161..d22ad5a 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,6 +1,6 @@
 -r ../requirements.txt
 
-pyTooling>=2.11.0
+pyTooling>=2.13.0, <3.0
 
 # Enforce latest version on ReadTheDocs
 sphinx >=5.3, <6.0