1. B. K. Koe, Fed. Proc.,30, 886 (1971).
2. A. Sjoerdsma, ibid., 908.
3. M. Schlesinger, N. Grossowicz, and N. Lichtenstein, Experientia,25, 14 (1969); M. Schlesinger, N. Grossowicz, and N. Lichtenstein, Israel J. Med. Sci.,7, 547 (1971).
4. B. Shohat et al., ibid.,8, 29 (1972).
5. Sigeshi Taezima, Kiedzo Kanao, and Masashi Sugiyama, Japanese Patent No. 30505 (1971); Ref. Zh. Khim., (1972).