19. Palefsky J. M., Holly E. A., Ralston M. L., Jay N. Prevalence and risk factors for human papillomavirus infection of the anal canal in human immunodeficiency virus (HIV)-positive and HIV-negative homosexual men. J Infect Dis. 1998 Feb;177(2):361–7.

20. Machalek D. A., Poynten M., Jin F., Fairley C. K., Farnsworth A., Garland S. M., Hillman R. J., Petoumenos K., Roberts J., Tabrizi S. N., Templeton D. J., Grulich A. E.. Anal human papillomavirus infection and associated neoplastic lesions in men who have sex with men: a systematic review and meta-analysis. Lancet Oncol. 2012 May;13(5):487–500.

21. Williams A. B., Darragh T. M., Vranizan K., Ochia C., Moss A. R., Palefsky J. M. Anal and cervical human papillomavirus infection and risk of anal and cervical epithelial abnormalities in human immunodeficiency virus-infected women. Obstet Gynecol. 1994 Feb;83(2):205–11.

22. Silverberg M. J., Lau B., Justice A. C., et al. Risk of anal cancer in HIV-infected and HIV-uninfected individuals in North America. Clin Infect Dis. 2012;54:1026–34.

23. Poynten I. M., Jin F., Templeton D. J., Law C., Roberts J., Cornall A., Molano L. M., Ekman D., McDonald R., Farnsworth A., Garland S. M., Fairley C. K., Hillman F. J., Grulich A. E. Clearance of anal HSIL is inversely related to persistent high-risk HPV – three year follow up results from the Study of Prevention of Anal Cancer (SPANC). Presented at 32nd Annual International Papillomavirus Conference, October 2018, Sydney, Australia.

24. Ryan O’Neal interview. Piers Morgan Tonight. June 20, 2011. Available at: https://www.youtube.com/watch?v=ABRQjjF5Mio. Accessed April 21, 2019.

25. Mazziota J. Marcia Cross is sharing her anal cancer story in the hopes of ending the “stigma.” People. March 27, 2019. Available at: https://people.com/health/marcia-cross-anal-cancer-story-end-stigma/. Accessed April 21, 2019.

26. Jannette Howard, Pink Ribbon Breakfast speech, Sydney, Australia. October 16, 2006. Available at: https://www.youtube.com/watch?v=szXd-iiy2r8.Accessed March 31, 2009.

27. Australian Academy of Science. Interview with Professor Ian Frazer, immunologist. Available at: https://www.science.org.au/learning/general-audience/history/interviews-australian-scientists/professor-ian-frazer-immunologist#12. Accessed April 2, 2019.

28. Cancer Australia. HPV vaccination uptake. Available at: https://ncci.canceraustralia.gov.au/prevention/hpv-vaccination-uptake/hpv-vaccination-uptake. Accessed March 3, 2020.