“Quantification of Total Phenol Concentration in Ethanol Extracts of Red and Black Betel Leaves Using UV-Vis Spectrophotometric Method: Penentuan Kandungan Total Fenol Dalam Ekstrak Etanol Daun Sirih Merah Dan Hitam Dengan Memanfaatkan Teknik Spektrofotometri”. Journal Pharmasci (Journal of Pharmacy and Science) 9, no. 1 (June 11, 2024): 29–33. Accessed October 26, 2025. https://ejournal.akfarsurabaya.ac.id/index.php/jps/article/view/388.