Sandberg, C., Stenquist, B., Rosdahl, I., Ros, A., Synnerstad, I., Karlsson, M., … Wennberg, A. (2006). Important factors for pain during photodynamic therapy for actinic keratosis. Acta Dermato-Venereologica, 86(5), 404–408. https://doi.org/10.2340/00015555-0098