diff --git a/docs/ref/contrib/gis/forms-api.txt b/docs/ref/contrib/gis/forms-api.txt
index c05cef65d0..472132cfbc 100644
--- a/docs/ref/contrib/gis/forms-api.txt
+++ b/docs/ref/contrib/gis/forms-api.txt
@@ -157,7 +157,7 @@ Widget classes
 
     .. attribute:: base_layer
 
-       .. versionadded:: 6.0
+        .. versionadded:: 6.0
 
         ``nasaWorldview``