Add link to PEP 236.
diff --git a/Doc/reference/simple_stmts.rst b/Doc/reference/simple_stmts.rst
index 6ae0317..beb4623 100644
--- a/Doc/reference/simple_stmts.rst
+++ b/Doc/reference/simple_stmts.rst
@@ -907,6 +907,11 @@
 a future statement, it will be in effect in the interactive session started
 after the script is executed.
 
+.. seealso::
+
+   :pep:`236` - Back to the __future__
+      The original proposal for the __future__ mechanism.
+
 
 .. _global: