1. N.N. Powell and C. Andrew: Proceedings of the Institution of Mechanical Engineers Part B- Journal of Engineering Manufacture, 206 (1992), No. 1, pp.41-47.
2. S. Matsubara: Journal of the Japanese Society of Technology of Plasticity, 35 (1994), pp.1311-1316.
3. M. Matsubara, S. Tanaka, and T. Nakamura: Jsme International Journal Series C-Dynamics Control Robotics Design and Manufacturing, 39 (1996), No. 1, pp.156-163.
4. K. Kitazawa, et al.: Journal of Japanese Institute of Light Metals, 46 (1996), pp.65-70.
5. H. Amino, et al.: Dieless NC forming of automotive service parts, Advanced Technology of Plasticity, 2002, Yokohama, Japan.