Piras, Franca, et al. “Human Papillomavirus Type Distribution and Correlation With Cyto-Histological Patterns in Women from Benin”. Italian Journal of Anatomy and Embryology, vol. 115, no. 1/2, Nov. 2010, p. 140, https://oajournals.fupress.net/index.php/ijae/article/view/4525.