diff --git a/docs/03-client-tools.md b/docs/03-client-tools.md
index 576e064..df9e5d9 100644
--- a/docs/03-client-tools.md
+++ b/docs/03-client-tools.md
@@ -31,6 +31,8 @@ EOF
 
 The [kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl). command line utility is used to interact with the Kubernetes API Server. Download and install `kubectl` from the official release binaries:
 
+Reference: [https://kubernetes.io/docs/tasks/tools/install-kubectl/](https://kubernetes.io/docs/tasks/tools/install-kubectl/)
+
 ### Linux
 
 ```