1. D.S. Wang A.P. Zhou Y.L. Yuan: Journal of Materials Processing Technology. Vol. 129(2002), p.237.
2. B.Z. Lü, Y.P. Ma, H.X. Fu and L.C. Wu, in: Proceedings of International Conference on Mechanical Transmissions, edtied by D.T. Qin/ Chinese Machine Press, Chongqing, (2001).
3. Y.J. Wu: Journal of Zhejiang University(Engineering Science), Vol. 38(2004), p.877.
4. L.C. Wu, Y.Y. Zheng, J.W. Zhao, etal: Manufacture theory and technology of profile connection (China coal industry publishing house, Beijing 2001).
5. J.H. Zhao, M.F. Wang: Elasticity& Finite Element(Wuhan University of Technology Press, Wuhan 2003).