1. Yu. A. Kazanskii, A. A. Vankov, and B. I. Inyutin, At. Energy Rev.,13, No. 4, 807 (1975).
2. A. I. Leipunskii et al., At. Energ.,36, No. 1, 3 (1974).
3. V. F. Efimenko and A. V. Shapar', Preprint FÉI-620, Physics and Power-Engineering Institute, Obninsk (1975).
4. E. N. Kuzin et al., Preprint FÉI-698, Physics and Power-Engineering Institute, Obninsk (1976).
5. V. M. Lityaev, V. A. Dulin, and Yu. A. Kazanskii At. Energ.,47, No. 1, 44 (1979).