Wiegell, Stine R., et al. “Pulse–Daylight–Photodynamic Therapy in Combination With Corticosteroid and Brimonidine Tartrate for Multiple Actinic Keratoses: A Randomized Clinical Trial”. Acta Dermato-Venereologica, vol. 99, no. 2, Nov. 2018, pp. 242-3, doi:10.2340/00015555-3049.