diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index e857c29..e64644f 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -19,7 +19,7 @@ We accept contributions via Pull Requests on [Github](https://github.com/thephpl
 
 - **One pull request per feature** - If you want to do more than one thing, send multiple pull requests.
 
-- **Send coherent history** - Make sure each individual commit in your pull request is meaningful. If you had to make multiple intermediate commits while developing, please squash them before submitting.
+- **Send coherent history** - Make sure each individual commit in your pull request is meaningful. If you had to make multiple intermediate commits while developing, please [squash them](http://www.git-scm.com/book/en/v2/Git-Tools-Rewriting-History#Changing-Multiple-Commit-Messages) before submitting.
 
 
 ## Running Tests