[Original 1975 Phong Reflection Model paper](http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.330.4718&rank=1)


[Scratchapixel](https://www.scratchapixel.com/lessons/3d-basic-rendering/phong-shader-BRDF)

[Nvidia lighting tutorial](http://developer.download.nvidia.com/CgTutorial/cg_tutorial_chapter05.html)

[3D Game Engine Programming - Jeremiah van Oosten](https://www.3dgep.com/texturing-lighting-directx-11/#Light_Properties)

[Stop Using Normal Matrix](https://lxjk.github.io/2017/10/01/Stop-Using-Normal-Matrix.html)

### Great books

Fundamentals of Computer Graphics, Fourth Edition - Steve Marschner, Peter Shirley

3D Graphics for Game Programming - JungHyun Han