diff --git a/README.md b/README.md
index 246a3f0..76e82de 100644
--- a/README.md
+++ b/README.md
@@ -89,7 +89,7 @@ These Python programs can be downloaded from GitHub at
 	* The Chirikov map, also known as the standard map, is a discrete itereated map with winding numbers and islands of stability.
 
 * StandMapHom.py: 
-	* Homoclinic tangle for the standard map.
+	* Homoclinic tangle for the standard map.  (See: https://galileo-unbound.blog/2020/08/24/henri-poincare-and-his-homoclinic-tangle/)
 
 * StandMapTwist.py: 
 	* The Standard Map in twist format  (See: https://galileo-unbound.blog/2019/10/14/how-number-theory-protects-you-from-the-chaos-of-the-cosmos/)