“Follow-up results of a randomized, double-blind, phase III, multi-center study to evaluate the safety and efficacy of BF-200 ALA versus placebo in field-directed treatment of mild to moderate AK with photodynamic therapy when using narrowband red light” (2019) SKIN The Journal of Cutaneous Medicine, 3, p. S49. doi:10.25251/skin.3.supp.49.