1. Ayala, A.R., Nisula, B.C., Chen, H.C., Hodgen, G.D., and Ross, G.T., 1978, Highly sensitive radioimmunoassay for chorionic gonadotropin in human urine, J. Clin. Endocrinol. Metab. 47: 767–773.
2. Bahl, O.P., 1969, Human chorionic gonadotropin. I. Purification and physicochemical properties, J. Biol. Chem. 244: 567–574.
3. Bahl, O.P., 1973, Chemistry of human chorionic gonadotropin, in: Hormonal Proteins and Peptides, Vol. 1 ( C.H. Li, ed.), pp. 171–199, Academic Press, New York.
4. Bahl, O.P., 1977, Chemistry and biology of human chorionic gonadotropin and its subunits, in: Frontiers in Reproduction and Fertility, Part II ( R.O. Greep, ed.), pp. 11–24, MIT Press, Cambridge.
5. Bahl, O.P., and Muralidhar, K., 1980, Current status of antifertility vaccines, in: Immunological Aspects of Infertility and Fertility Regulation (G.B.F. Schumacher and D.S. Dhindsa, eds.), pp. 225–257, Elsevier/North-Holland, Amsterdam (in press).