1. 3) T. Inazumi, S. Kasama, K. Sato, M. Sasaki and T. Tanaka : Proc. the 5th International Symposium on Agglomeration at Brighton, Sep. (1989), p. 59
2. 5) Dietrich Stauffer : Introduction to Percolation Theory (1987), p. 50 [Taylor & Francis Ltd., London]
3. 7) S. Kasama, T. Inazumi and K. Sato : Proc. the 6th International Iron and Steel Congress, Nagoya, 2 (1990), p. 118