Add documentation reference

README.md

@@ -12,6 +12,12 @@ collection.
 
 Requires the [activation](https://github.com/marketplace/actions/unity-activate) step.
 
+## Documentation
+
+See the 
+[Unity Actions](https://github.com/webbertakken/unity-actions)
+collection repository for workflow documentation and reference implementation.
+
 ## Usage
 
 Create or edit the file called `.github/workflows/activation.yml` and add a job to it.