diff --git a/Lib/decimal.py b/Lib/decimal.py
index 24bd85b4935..1fe938f06c4 100644
--- a/Lib/decimal.py
+++ b/Lib/decimal.py
@@ -132,6 +132,7 @@
 ]
 
 __version__ = '1.70'    # Highest version of the spec this complies with
+                        # See http://speleotrove.com/decimal/
 
 import copy as _copy
 import math as _math