Maniscalco, M., G. Noto, L. Zichichi, R. Rinaldi, A. Milano, and A. Patrizi. “Mongolian Spot. Incidence and Natural History in Western Sicily.”. European Journal of Pediatric Dermatology, vol. 14, no. 3, Sept. 2004, pp. 137-40, https://ejpd.com/index.php/journal/article/view/274.