1. K.J. Weinmann and R.J. Shippell: Sixth North American Metal Working Research Conference Proceeding (May 1978), p.220.
2. C. Magnusson and Z. Tan: Proceedings of 16th Biannual IDDRG Congress (May 1990), p.363.
3. Y.M. Huang, H. Takizawa, A. Makinouchi and T. Nakagawa: Spring Proceedings on Plastic Working (1989), p.275.
4. Y.M. Huang, Y.H. Lu and A. Makinouchi: J. of Mater. Proc. Tech. Vol. 35 (1992), p.129.
5. H. Ogawa, A. Makinouchi, H. Takizawa and N. Mori: Advanced Technology of Plasticity Proceedings of Fourth International Conference on Technology of Plasticity (1993), p.1641.