1. Lack of Evidence of Sexual Transmission of Hepatitis C Virus in a Prospective Cohort Study of Men Who Have Sex With Men
2. J. M. Berry, and J. M Palefsky . (1998 ). Anogenital neoplasia and HIV . HIV InSite Knowledge Base Chapter . Retrieved March 1, 2005, from, http://hivinsite.ucsf.edu/InSite.jsp?page=kb-o6doc=kb=06-04-02