#24584: replace dead link with pointer to archive.org.
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index bdb18bc..e7e3262 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -47,7 +47,7 @@
Module :mod:`doctest`
Another test-support module with a very different flavor.
- `Simple Smalltalk Testing: With Patterns <http://www.XProgramming.com/testfram.htm>`_
+ `Simple Smalltalk Testing: With Patterns <https://web.archive.org/web/20150315073817/http://www.xprogramming.com/testfram.htm>`_
Kent Beck's original paper on testing frameworks using the pattern shared
by :mod:`unittest`.