Fix ref

Author: markshannon

peps/pep-0805.rst

@@ -91,7 +91,7 @@ An object's ``__shared__`` state can be one of the following:
 * Synchronized: A special state for some builtin objects.
   All operations on the object are protected by an internal mutex, so no external synchronization is needed.
 
-\* Strictly, a single "super thread". See :ref:`super-thread` below.
+\* Strictly, a single "super thread". See :ref:`super-threads` below.
 
 The ``__shared__`` attribute is read-only.