1. Aristotle, Historia Animalum, English translation by Thompson, D'A. W., 631 (Clarendon Press, Oxford).
2. Tandler, J., and Grosz, S., Die Biologischen Grundlagen der Sekundaren Geschlechtscharaktere, 31 (Springer, Berlin, 1913). Goss, R. J., in Mechanisms of Hard Tissue Destruction (edit. by Sognnaes, R. F.), 339 (AAAS Publication No. 75, Washington, 1963).
3. Blauel, G., Endokrinologie, 15, 321 (1935); ibid., 17, 369 (1936).
4. Goss, R. J., J. Embryol. Exp. Morphol., 9, 342 (1961); Advances in Biology of Skin (edit. by Montagna, W., and Billingham, R. E.), 5, 194 (Pergamon Press, London, 1964).
5. Wislocki, G. B., Aub, J. C., and Waldo, C. M., Endocrinology, 40, 202 (1947); Wislocki, G. B., in Ageing in Transient Tissues (edit. by Wolstenholme, G. E. W., and Millar, E. C. P.), 2, 176 (Ciba Foundation Colloquia on Ageing, 1956); Tachezy, R., Saugetierkl. Mitt., 4, 103 (1956).