Other mammals have oral sex
http://www.livescience.com/46364-brown-bears-caught-performing-oral-sex.html
History of oral sex
Tannahill, Reay. Sex in History. Stein and Day, NY, 1980.
Clarke, John R. Roman Sex. Harry N. Abrams, NY 2003.
Doniger, Wendy and Sudhir Kakar. Vatsyayana Kamasutra. Oxford University Press, NY, 2002.
Berkowitz, Eric. Sex and Punishment. Counterpoint Press, Berkeley, CA 2012.
Armstrong, David and Liz Metzger Armstrong. The Great American Medicine Show. Prentice Hall, NY, 1991.
Prevalence of oral sex
Herbenick, D. et al. “Sexual Behavior in the United States: Results from a National Probability Sample of Men and Women Ages 14-94,” Journal of Sexual Medicine (2010) 7(suppl):255.
Women’s insecurities about vaginal odor
Grimley, D.M. et al. “Vaginal Douches and Other Feminine Hygiene Products: Women’s Practices and Perceptions of Product Safety,” Maternal and Child Health (2006) 10:303.
Martino, J.L. and S.H. Vermund. “Vaginal Douching: Evidence for Risks or Benefits to Women’s Health,” Epidemiologic Reviews (2002) 24:109.
Stephens-Davidowitz, S. “Searching for Sex,” New York Times, Jan. 25, 2015.
Deep Throat cost and revenue
https://en.wikipedia.org/wiki/Deep_Throat_(film)
