1Alberts, Gartska D. S., J, Hayes R. E., D. A. Signori. Understand- ing Information Age Warfare, US Department of Defense, Command and Control Research Program, 2001.
2Davidoff, G.,P. Samak, Volette A.. Elementary Number Theory, Group Theory, and Ramanujan Graphs [M].Cambridge, UK: Cambridge University Press, 2003.
3Yang, Miin-Shen Liu, Hsien-Hsiung. Fuzzy clustering proce- dures for conical fuzzy vector data [J].Fuzzy Sets and Systems, 1999, 106 (2): 189-200.