1. Environment Agency of Japan, Cabinet Order 207. (1972).
2. Environment Agency of Japan, Cabinet Order 242. (1976).
3. M. Smisek and S. Cerny, “Active Carbon” (Elsevier, Amsterdam, London, New York, 1970) Ch. 5.
4. M. Sugiura, H. Hayashi and T. Suzuki, Clay Sci.
8 (1991) 87.
5. M. Sugiura, K. Fukumoto and S. Inagaki, ibid. (1991) 129.