diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 94db780c4b..24cc2ccf6a 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -23,7 +23,9 @@ We've tried to make editing an existing file as simple as possible.
 
        ![GitHub Web, showing the Pencil icon in the red box](images/pencil-icon.png)
 
-3.	Using markdown language, make your changes to the topic. For info about how to edit content using markdown, see http://aka.ms/windows-op-guide.
+3.	Using markdown language, make your changes to the topic. For info about how to edit content using markdown, see:
+    - **If you're linked to the Microsoft organization in GitHub:** [Windows Open Publishing Guide Home](http://aka.ms/windows-op-guide)
+    - **If you're external to Microsoft:** [Mastering Markdown](https://guides.github.com/features/mastering-markdown/) 
 
 4.	Make your suggested change, and then click **Preview Changes** to make sure it looks correct.