Mendonça Sanches, M., A. R. Travassos, and L. Soares-de-Almeida. “An Odd Collision Tumor – Dermatofibroma Plus Nevus”. Journal of the Portuguese Society of Dermatology and Venereology, Vol. 74, no. 1, Apr. 2016, pp. 93-94, doi:10.29021/spdv.74.1.523.