1. Zhao Wansheng Technology of EDM Pulse (M). Harbin: Harbin Institute of Technology Press, (2005).
2. Zhao wansheng, Zhu Di, Wang Henglong, Gongming. Research and Development of Nontraditional Machining in China. International Journal OF Electrical Machining. 2001(3)1~6(In Chinese).
3. Guo Jinquan. The study on difficult-to-process material discharge machining pulse power. Dissertation for Master degree, Harbin: Harbin industrial university, 2006: 5~8, (In Chinese).
4. Yang X., Tang Y.Y. , Cao J. Embedding torus in hexagonal honeycomb torus, Computers & Digital Techniques, IET , vol. 2, no. 2, pp.86-93, March (2008).
5. Zhai Dehai , Zhai Zhenhui. Analyze, study and optimize of electrical discharge machining process effect. Mold manufacturing, 2002(14): 39~41(In Chinese).