1. P. Gribler et al., Nucl. Applic., No. 5, 297 (1968).
2. V. L. Anan'ev et al., At. �nerg.,20, 106 (1966).
3. V. N. Kononov et al., Prib. Tekh. �ksp., No. 6, 51 (1969).
4. Yu. A. Aleksandrov, Yu. V. Ryabov, and G. S. Samosvat, Preprint JINR R-2014 [in Russian], Dubna (1965).
5. H. Darrien et al., Nucl. Data for Reactors, Vol. 11, IAEA, Vienna (1967), p. 195.