Leba, Maria Aloisia Uron, Maria Benedikta Tukan, and Faderina Komisia. “PH Indicator Paper by Immobilizing Turmeric Rhizome Ethanol Extract on Filter Paper”. Sains Natural: Journal of Biology and Chemistry 12, no. 2 (April 29, 2022): 45–53. Accessed May 18, 2026. https://ejournalunb.ac.id/JSN/article/view/377.