1. Hafez, E. S. E., and Prasad, M. R. N., in: Human semen and fertility regulation in men, p. 31. Ed. E. S. E. Hafez. The C. V. Mosby Company, Saint Louis 1976.
2. Orgebin-Crist, M. C., and Tichenor, P. L., Nature245 (1973) 328.
3. Eliasson, R., Biochem. J.98 (1966) 242.
4. Doeg, K. A., Polomski, L. L., and Doeg, L. H., Endocrinology90 (1972) 1633.
5. Umapathy, E., Manimekalai, S., and Govindarajulu, P., Indian J. Physiol. Pharmac.23 (1979) 179.