References

1. An Image Synthesizer, Ken Perlin.
   Computer Graphics (Proceedings of SIGGRAPH 85). 19(3), pp. 287-296, 1985.
2. Shade trees, Robert L. Cook.
   Computer Graphics (Proceedings of SIGGRAPH 84). 18(3), pp. 223-231, 1984.
3. On the Algebraic and Geometric Foundations of Computer Graphics, R.N. Goldman
   Transactions on Graphics, 21 (2002): 1-35
4. An Introduction to Ray tracing, by Andrew S. Glassner
   Morgan Kaufmann, 1989
5. The Ray Tracing Kernel, David Kirk and James Arvo.
   Proceedings of Ausgraph '88. pp. 75-82, 1988.
6. Stochastic Sampling in Computer Graphics, Robert L. Cook.
   ACM Transactions on Graphics. 5(1), pp. 51-72, 1986.
7. Distributed Ray Tracing, R. Cook and T. Porter and L. Carpenter.
   Computer Graphics (Proceedings of SIGGRAPH 84). 18(3), pp. 137-145, 1984.