Phototesting as an objective measure of improvement in erythropoietic protoporphyria.
Mathews-Roth MM, Kass EH, Fitzpatrick TB, Pathak MA, Harber LC. Phototesting as an objective measure of improvement in erythropoietic protoporphyria. Arch Dermatol. 1979 Dec; 115(12):1391-2.