diff --git a/free-programming-books.md b/free-programming-books.md
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 * [OpenGL Insights](http://openglinsights.com) (chapters 22, 23, 28, 33, 39)
 * [ShaderX series](http://tog.acm.org/resources/shaderx/)
 * [Tutorials for modern OpenGL](http://www.opengl-tutorial.org/)
+* [OpenGL Programming Guide (The Red Book)](http://fly.srk.fer.hr/~unreal/theredbook/)
 
 
 ###Graphics User Interfaces