1. O. Tokunaga, N. Nishimura, N. Suzuki and M. Washino, Radiat. Phys. Chem., 11, 117 (1978).
2. O. Tokunaga and N. Suzuki, Radiat. Phys. Chem., 24, 145 (1984).
3. D. Tai, IAEA workshop on radiation utilization, asia and pacific section (1966).
4. O. Tokunaga, Sci. Technol. Jpn., 16(65), 47 (1998).
5. A.G. Chmielewski, E. Iller, J. Licki and B. Tymiński, INCT Annual Report, 119 (1998).