diff --git a/trello/card.py b/trello/card.py
index aab24d75..3a8184dc 100644
--- a/trello/card.py
+++ b/trello/card.py
@@ -16,6 +16,8 @@ class Card(object):
     """
     Class representing a Trello card. Card attributes are stored on
     the object
+    
+    https://developers.trello.com/advanced-reference/card
     """
 
     @property