diff --git a/dist/doc/extend.md b/dist/doc/extend.md
index 0a3506a3..e216b975 100644
--- a/dist/doc/extend.md
+++ b/dist/doc/extend.md
@@ -167,7 +167,7 @@ Add this function after `ga` is defined:
 
 ### Track page scroll
 
-Add this function after `ga` is defined:
+Add this function after `ga` is defined. Note, the following snippet requires jQuery.
 
 ```js
 $(function(){
diff --git a/src/doc/extend.md b/src/doc/extend.md
index 0a3506a3..e216b975 100644
--- a/src/doc/extend.md
+++ b/src/doc/extend.md
@@ -167,7 +167,7 @@ Add this function after `ga` is defined:
 
 ### Track page scroll
 
-Add this function after `ga` is defined:
+Add this function after `ga` is defined. Note, the following snippet requires jQuery.
 
 ```js
 $(function(){