Fixing invalid link to a Ruby resource

free-programming-books.md

@@ -1575,7 +1575,7 @@ See also [TeX](#tex)
 * [Ruby Programming](http://www.linuxtopia.org/online_books/programming_books/ruby_tutorial/)
 * [Ruby User's Guide](http://www.rubyist.net/~slagell/ruby/)
 * [The Bastards Book of Ruby](http://ruby.bastardsbook.com/)
-* [The Little Book Of Ruby](http://www.sapphiresteel.com/The-Little-Book-Of-Ruby)
+* [The Little Book Of Ruby](http://www.sapphiresteel.com/ruby-programming/The-Little-Book-Of-Ruby.html)
 * [The Unofficial Ruby Usage Guide (at Google)](http://www.caliban.org/ruby/rubyguide.shtml) - Ian Macdonald
 * [Why's (Poignant) Guide to Ruby](http://mislav.uniqpath.com/poignant-guide/) ([mirror](http://www.scribd.com/doc/2236084/Whys-Poignant-Guide-to-Ruby))