diff --git a/docs/source/index.rst b/docs/source/index.rst
index 0391989..621a93a 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -36,7 +36,7 @@ from ROMs.
 
 
     .. toctree::
-        :caption: PL/1
+        :caption: PL1
         :maxdepth: 3
         :hidden: