diff --git a/README.md b/README.md
index e4ad8bb..8a8286e 100644
--- a/README.md
+++ b/README.md
@@ -54,3 +54,8 @@ Due to limitation of NFS4.0, idmapping is too hard (mismatch between server and
 3. When writing files, remember to chown afterward
 
 For plex server, I need to align LXC's uid and gid with Synology
+
+## Reference
+
+* [NFS: Overview and Gotchas](http://www.troubleshooters.com/linux/nfs.htm)
+* [How to setup NFS server and client](https://codeyarns.com/2013/03/17/how-to-setup-nfs-server-and-client/)