van der Willigen, AH, Peereboom-Wynia JD, JC van der Hoek, Mulder PG, TH van Joost, and E Stolz. “Hair Root Studies in Patients Suffering from Primary and Secondary Syphilis”. Acta Dermato-Venereologica 67, no. 3 (May 1, 1987): 250–254. Accessed November 3, 2024. https://medicaljournalssweden.se/actadv/article/view/6663.