1. Axelrod, L. R.: Recent Progr. Hormone Res. 1954, 9, 69.
2. Bauld, W. S.: Biochem. J. 1956, 63, 488.
3. Brown, J. B.: ibid. 1955, 60, 185.
4. Brown, J. B.: Personal communication, 1956.
5. Faermark, S. E.: Probl. Zooteh. exp. Endocrinol. 1935, 2, 48. Cited in: Cowie, A. T.: Pregnancy Diagnosis Tests. A Review. Common-wealth Agricultural Bureau Joint Publication No. 13. Great Britain, 1948, 283.