YAZID, Edy Agustian; WAFI, Abdul; WULANDARI, Agustin Eka. Spectrophotometric Methods for the Determination of Caffeine in Beverages Use Solvent Extraction Techniques and Adsorption of Activated Carbon. Journal of Tropical Pharmacy and Chemistry, [S. l.], v. 5, n. 4, p. 338–346, 2021. DOI: 10.25026/jtpc.v5i4.308. Disponível em: https://jtpc.jurnalfamul.com/index.php/jtpc/article/view/308. Acesso em: 9 sep. 2026.