diff --git a/sk1/README.md b/sk1/README.md
index 34cca95..fa721d9 100755
--- a/sk1/README.md
+++ b/sk1/README.md
@@ -60,3 +60,7 @@ https://nudges.works
 ```bash
 ./remove-app.sh
 ```
+
+## External Sources
+- GKE ManagedCertificate guide  
+- MongoDB Atlas docs
\ No newline at end of file