Zulkarnain, A. K., J. Jumina, G. T. Kharismawati, and F. A. Larasati. “Optimization of Gelling Agent and Sunscreen Activity Test of 4-OH-Chalcone Gel by In Vitro Method”. Indonesian Journal of Pharmacy, Vol. 34, no. 1, Jan. 2023, pp. 112-9, doi:10.22146/ijp.3300.