Update README.md

Author: capnramses

README.md

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 # Anton's OpenGL 4 Tutorials book demo code
 
-This series of demos accompanies the e-book "Anton's OpenGL 4 Tutorials":
-[antongerdelan.net/opengl](http://antongerdelan.net/opengl/)
+> [!NOTE]\
+> This series of demos accompanies the e-book "Anton's OpenGL 4 Tutorials":
+> [antongerdelan.net/opengl](http://antongerdelan.net/opengl/)
 
 ## Info