1. Hecht, H.: Venereal diseases in homosexuals. Acta. dermat.-venereol.37: 182, 1957.
2. Hermans, E. H., Sr., and P. de Cock: Homosexuality and venereal diseases. Dermatologica.127: 278, 1963.
3. Hollings, R. M.: Symphilitic ulcers of the anus. Proc. Roy. Soc. Med.54: 730, 1961.
4. Jackson, C. C.: Syphilis. The role of the homosexual. Canad. Med. Serv. J.19: 631, 1963.
5. Kvorning, S. A.: Clinical comments on the start of an epidemic of syphilis. Brit. J. Ven. Dis.39: 261, 1963.