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2. 2) S. Komatsu, T. Kumano, K. Ohtsuka, K. Kaneko, N. Sano and T. Sohma: Collected Abstract of the 1981 Autum Meeting of ISIJ, p. 669 (in Japanese).
3. 3) S. Eketorp: The 2nd Japan-Sweden Joint Symp. on Ferrous Metallurgy, Ed. by ISIJ, ISIJ, Tokyo, (1978), p. 1.
4. 4) M. Nakamura and N. Tokumitsu: Tetsu-to-Hagané, 3 (1981), 50 (in Japanese).
5. 5) Y. Kamiya, Y. Sanada and A. Tomita: Coal and Heavy Oil, Kodansha, (1979), p. 64.