diff --git a/manual/source/installation.rst b/manual/source/installation.rst
index 40455ee434..d8c9313be0 100644
--- a/manual/source/installation.rst
+++ b/manual/source/installation.rst
@@ -201,7 +201,7 @@ Versioning (Tags)
 -----------------
 
 Versioning of each of the NXDL files, as well as the 
-complete set of NXDL files is now described in wiki [#]_
+complete set of NXDL files is now described in the wiki [#]_
 of the NeXus definitions repository [#]_.  
 Please see that wiki for complete information.