Siu, S. Y., G. M. Ferzli, and N. Brody. “Topical Green Tea Polyphenols and Caffeine As a Treatment for Acne Vulgaris”. SKIN The Journal of Cutaneous Medicine, vol. 1, no. 3.1, Oct. 2017, p. s55, doi:10.25251/skin.1.supp.54.