1. N. Ma, P. Hu, G. Z. Shen, et al: AIP Conference Proceedings, Plenary lecture of NUMIFORM2010, 2010, 18-26.
2. Y. Zhang, P. Zhu, GL. Chen: Thin-walled Structures, 45(2007), 670-676.
3. H. T. Parisa, N. Mossa: Thin-walled Structures 44(2006), 407-414.
4. N. Ma, P. Hu, W. Guo: Automobile & Parts, 45 (2009), 28-30(in Chinese).
5. A. Yadav, T. Altan: Stamping Journal, 12(2006), 40-42.