Figueiró Filho, Ernesto Antonio, et al. “Syphilis and Pregnancy: A Two-Period (2006 and 2011) Comparative Study of a Puerperal Women Population”. Brazilian Journal of Sexually Transmitted Diseases, vol. 24, no. 1, Feb. 2023, pp. 38-43, https://www.bjstd.org/revista/article/view/1039.