Fix link.

mahmoudhossam · mahmoudhossam · commit bdf04941f88d · 2012-05-07T16:32:04.000+03:00
diff --git a/docs/intro/learning.rst b/docs/intro/learning.rst
@@ -76,7 +76,7 @@ additional resource or reference will be helpful.
 
 More information about test driven development can be found at these resources:
 
-    `Test Driven Development <http://en.wikipedia.org/wiki/Test-driven_development>`
+    `Test Driven Development <http://en.wikipedia.org/wiki/Test-driven_development>`_
 
 
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