diff --git a/readme.md b/readme.md
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@@ -385,7 +385,7 @@ Creative coding is a different discipline than programming systems. The goal is
 - [Shaderific GLSL](http://www.shaderific.com/glsl/) - OpenGL ES shading language reference.
 - [The Book of Shaders Glossary](https://thebookofshaders.com/glossary/) - Shader glossary by theme.
 - [gltut glossary pages: 1](https://paroj.github.io/gltut/Basics/Intro%20Glossary.html), [2](https://paroj.github.io/gltut/Basics/Tut01%20Glossary.html), [3](https://paroj.github.io/gltut/Basics/Tut02%20Glossary.html), [4](https://paroj.github.io/gltut/Positioning/Tut04%20Glossary.html), [5](https://paroj.github.io/gltut/Positioning/Tut05%20Glossary.html), [6](https://paroj.github.io/gltut/Positioning/Tut06%20Glossary.html), [7](https://paroj.github.io/gltut/Positioning/Tut07%20Glossary.html), [8](https://paroj.github.io/gltut/Positioning/Tut08%20Glossary.html) - OpenGL 3D programming glossary.
-- [Canvas Cheatsheet](https://skilled.co/html-canvas/images/HTML_Canvas_Cheatsheet.pdf) - Quick and visual canvas cheatsheet.
+- [Canvas Cheatsheet](https://web.archive.org/web/20171226205420/https://skilled.co/html-canvas/) - Quick and visual canvas cheatsheet.
 - [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.