Ibrahim, Z., Dimitrova, Z., Georgiev, S., Madzharov, V., & Titeva, S. (2010). Use of cosmetic products contanning extract of Marigold (Calendula officinalis) in cases of acne at the educational and beauty center "Top Beauty - Sofia. Cosmetic treatment of acne. Scripta Periodica, 13 (4), 3-9.