1. D. E. Knuth, The TEX book (Addison-Wesley Publishing Company, 1986).
2. CTAN. Comprehensive TEX Archive Network. URL: http://www.ctan.org/
3. Wolfram Mathematica. URL: http://www.wolfram.com/mathematica/
4. WolframAlpha computational knowledge engine. URL: http://www.wolframalpha.com/
5. S. Wolfram, A New Kind of Science (WolframMedia, Inc., 2002).