Ferdinal, Norman. “PEMURNIAN CATECHIN DARI GAMBIR KOTO PANJANG, PESISIR SELATAN”. Jurnal Riset Kimia 5, no. 1 (February 12, 2015): 40. Accessed April 20, 2024. http://jrk.fmipa.unand.ac.id/index.php/jrk/article/view/177.