Anjan Chatterjee, The Aesthetic Brain: How We Evolved to Desire Beauty and Enjoy Art (New York: Oxford University Press, 2013), p. 88.

Jenny Wade, Transcendent Sex: When Lovemaking Opens the Veil (New York: Gallery Books; 2004).

Antoine Mazieres, Mathieu Trachman, Jean-Philippe Cointet, Baptiste Coulmont, and Christophe Prieur, «Deep Tags: Toward a Quantitative Analysis of Online Pornography», Porn Studies 1, nos. 1–2 (2014): 80–95.