1. 1) Ch. Yamauchi: Testu-to-Hagané, 75 (1989), 1237.
2. 2) Ch. Yamauchi, T. Fujisawa and H. Fukuyama: Proc. Fall Meet. Min. Mater. Process Inst. Jpn., Kyoto, October, (1989), K-1.
3. 3) M. Koiwa: Bull. Japan Inst. Metals, 6 (1967), 159.
4. 4) T. Okabe and A. G. Guy: Metall. Trans., 1 (1970), 2705.
5. 5) O. N. Carlson, F. A. Schmidt and D. T. Peterson: J. Less-Common Metals, 10 (1966), 1.