diff --git a/doc/sphinx/compiling/source-code.rst b/doc/sphinx/compiling/source-code.rst
index 565ab0d91..6e281dbeb 100644
--- a/doc/sphinx/compiling/source-code.rst
+++ b/doc/sphinx/compiling/source-code.rst
@@ -15,6 +15,7 @@ Stable Release
   Then, check out the tag of the most recent stable version::
 
     git checkout tags/v2.4.0
+    git submodule update
 
   A list of all the tags can be shown by::
 
@@ -37,6 +38,7 @@ Beta Release
 * **Option 1**: Check out the tag with the most recent beta release::
 
     git checkout tags/v2.4.0b1
+    git submodule update
 
   Note that the most recent beta version might be older than the most recent
   stable release. A list of all the tags, including stable and beta versions can
@@ -48,6 +50,7 @@ Beta Release
   next minor release of the stable version::
 
     git checkout 2.4
+    git submodule update
 
   This branch has all the work on the 2.4.x version of the software.