1. Li Qingfeng: Fracture Mechanics and its Engineering Application (Harbin Engineering University Press, Harbin China 2007).
2. Fu jiansan: Journal of North China Institute of Technolgy, Vol. 21(2000), pp.118-120. (In Chines).
3. Seung-Kee Koh: International Journal of Fatigue, Vol. 22(2000), pp.717-726.
4. Chen Aijun, Xu Cheng, Hu Xiaoqiu: Journal of Nanjing University of Science and Technology, Vol. 26(2002), pp.430-433. (In Chines).
5. Wang Xucheng, Shao Ming. Principles of FEM and numerical method (Tsinghua university press, Beijing 1997).