J. J. Vega-Castillo, S. Saenz-Guirado, M. L. Vega-Castillo, and R. Ruiz-Villaverde, “Umbilical Endometriosis: A New Dermoscopic Pattern”, Dermatol Pract Concept, vol. 12, no. 1, p. e2022023, Feb. 2022, doi: 10.5826/dpc.1201a23.