diff --git a/README.md b/README.md
index a45126a..d2a0dd4 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,7 @@
 
 Bash + Python ipset list updater from a JSON list of ipv4 and subnets
 * Based on [Firehol](https://iplists.firehol.org/) work
+* Shorewall documentation here : http://shorewall.org/ipsets.html
 
 ```
 {