N. F. Rupa, S. I. Gama, and I. Ahmad, “Validasi Metode dan Penetapan Kadar Kafein Menggunakan Spektrofotometri UV-Vis: Validation of the Method and Determination of Caffeine Levels Using UV-Vis Spectrophotometry”, Proc. Mul. Pharm. Conf., vol. 18, no. 1, pp. 109–115, Dec. 2023.