Yunarto, N. et al. 2023. Development and Validation of a High-Performance Liquid Chromatography-Based Method for Catechin Isolated from the Leaves of Gambir (Uncaria gambir Roxb): http://www.doi.org/10.26538/tjnpr/v7i3.16. Tropical Journal of Natural Product Research (TJNPR). 7, 3 (Apr. 2023), 2569–2573.