Add some internal links.
diff --git a/Doc/glossary.rst b/Doc/glossary.rst
index 4b0ab70..a051fe8 100644
--- a/Doc/glossary.rst
+++ b/Doc/glossary.rst
@@ -27,7 +27,7 @@
:ref:`2to3-reference`.
abstract base class
- Abstract Base Classes (abbreviated ABCs) complement :term:`duck-typing` by
+ :ref:`abstract-base-classes` complement :term:`duck-typing` by
providing a way to define interfaces when other techniques like
:func:`hasattr` would be clumsy. Python comes with many built-in ABCs for
data structures (in the :mod:`collections` module), numbers (in the