Valletta, E., et al. “Langerhans Cell Histiocytosis in a Child With a Perianal Skin Lesion and Constipation”. European Journal of Pediatric Dermatology, vol. 18, no. 2, June 2008, pp. 70-71, https://ejpd.migration.pkpps03.publicknowledgeproject.org/index.php/journal/article/view/505.