diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index a860a53..4ef0ca4 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -147,8 +147,12 @@
    inherit from both :meth:`Set` and :meth:`Hashable`, then define
    ``__hash__ = Set._hash``.
 
-(For more about ABCs, see the :mod:`abc` module and :pep:`3119`.)
+.. seealso::
 
+   * `OrderedSet recipe <http://code.activestate.com/recipes/576694/>`_ for an
+     example built on :class:`MutableSet`.
+
+   * For more about ABCs, see the :mod:`abc` module and :pep:`3119`.
 
 
 .. _deque-objects: