diff --git a/README.md b/README.md
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@@ -272,7 +272,7 @@ Creative coding is a different discipline than programming systems in which the
 - [WebGL Cheatsheet](https://www.khronos.org/files/webgl/webgl-reference-card-1_0.pdf) - WebGL 1.0 API reference card.
 - [Glossary of Computer Graphics](https://en.wikipedia.org/wiki/Glossary_of_computer_graphics) - Glossary of terms relating computer graphics.
 - [GLSL Reference Guide](http://www.cs.cmu.edu/afs/cs/academic/class/15462-f10/www/lec_slides/glslref.pdf) - OpenGL Shading Language quick reference guide.
-- [3D Maths Cheat Sheet](http://antongerdelan.net/teaching/3dprog1/maths_cheat_sheet.pdf) - 
+- [3D Maths Cheat Sheet](http://antongerdelan.net/teaching/3dprog1/maths_cheat_sheet.pdf) - Math cheatsheet by Anton Gerdelan, from his OpenGL book.
 - [docs.GL](http://docs.gl/) - Improvement of the official OpenGL documentation.
 - [OpenGL Shading Language](https://www.khronos.org/opengl/wiki/OpenGL_Shading_Language) - Khronos Group GLSL wiki.
 - [OpenGL 4.3 Reference Card](https://www.khronos.org/files/opengl43-quick-reference-card.pdf) - PDF Reference Card for the OpenGL 4.3 API.