Singh, S. K., T. Rai, T. Sharma, and A. Prabhu. “Multiple Umbilicated Papulonodular Lesions in an Immunocompetent Lady”. Journal of Pakistan Association of Dermatologists, vol. 23, no. 1, Dec. 2016, pp. 113-4, doi:10.66344/jpad.23.1.2013.277.