diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 58a5af58c..30a887b77 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -6,7 +6,7 @@ version: 2
 
 # Build pdf
 formats:
-  -pdf
+  pdf
   
 # Set the version of Python and other tools you might need
 build: