1. 1)T. Misawa, Bulletin of the Japan Institute of Metals, 24, pp.201-210(1985).
2. 2)K. Kojima, T. Yamada, T. Nigorikawa, K. Tachibana and G. Okamoto, Boshoku-Gijutsu(presently Zairyo-to-Kankyo), 23, p.595(1972).
3. 3)T. Nigorikawa, K. Kojima and G. Okamoto, Boshoku-Gijutsu(presently Zairyo-to-Kankyo), 26, p.67(1977).
4. 4)K. Miyata and S. Asakura, Chemistry and industrial chemistry, 1999, pp.445-450(1999).
5. 6)T. Fujii, T. Kodama and H. Baba, Boshoku-Gijutsu (presently Zairyo-to-Kankyo), 31, p.637(1982).