1. 1) K. Hirota, T. Nakagawa, S. Takeda, Y. Hashi and M. Tada: Mitsubishi Heavy Indust. Tech. Rev., 44 (2007), No. 3, 28.
2. 2) I. Kozasu: Seigyo Atsuen · Seigyo Reikyaku, Chijin Shokan, Tokyo, (1997), 17.
3. 3) H. Matsubara, T. Osuka, I. Kozasu and K. Tsukada: Tetsu-to-Hagané, 58 (1972), 1848.
4. 4) N. Tabata, T. Shiga, A. Kamata, T. Tanaka, K. Hirose and H. Misawa: Tetsu-to-Hagané, 63 (1977), S797.
5. 5) N. Nakata, T. Kuroki, A. Fujibayashi and Y. Utaka: Tetsu-to-Hagané, 99 (2013), 635.