1. Uchihori Hideo,Clean Steel, p. 3, ISIJ, Tokyo (1988).
2. Sasabe Minoru,Recent Progress in Steelmaking Technology for High Purity Steel, p. 1, ISIJ, Tokyo (1992).
3. N. Bessho, H. Yamasaki, T. Fuji, T. Nozaki and S. Hiwasa,ISIJ Int. 32, 157 (1992).
4. M. L. Turpin and J. F. Elliott,J. Iron and Steel Inst., March, 217 (1966).
5. Jung-Hyun Park, Young-Hyun Paik, Woo-Young Yoon and Dong-Sik Kim,J. Kor. Inst. Met. & Mater. 35, 1165 (1997).