diff --git a/free-programming-books.md b/free-programming-books.md
index 62b144ef2f1a25b4793ef0d4ed3cc6ab7ef8be4b..532afcd865fa38e7e9079cb557c64ed3eeaf05a6 100755
--- a/free-programming-books.md
+++ b/free-programming-books.md
@@ -1315,4 +1315,4 @@ See also [LaTeX](#latex)
 ###xBase (dBase / Clipper / Harbour)
 * [Application Development with Harbour](http://en.wikibooks.org/wiki/Application_Development_with_Harbour)
 * [CA-Clipper 5.2 Norton Guide](http://www.ousob.com/ng/clguide/)
-* [Clipper Tutorial: a Guide to Open Source Clipper(s)](http://en.wikibooks.org/wiki/Clipper_Tutorial:_a_Guide_to_Open_Source_Clipper(s))
+* [Clipper Tutorial: a Guide to Open Source Clipper(s)](http://en.wikibooks.org/wiki/Clipper_Tutorial:_a_Guide_to_Open_Source_Clipper(s%29)