KRAJEWSKI, Piotr K.; SZEPIETOWSKI, Jacek C. Blue-brownish Nodule in the Umbilical Area: A Quiz. Acta Dermato-Venereologica, [S. l.], v. 103, p. adv18368, 2023. DOI: 10.2340/actadv.v103.18368. Disponível em: https://medicaljournalssweden.se/actadv/article/view/18368. Acesso em: 31 may. 2026.