“Concentration Effect of MgO K2O Catalyst on Transesterification of Castor Seed (Ricinus Communis) Oil: Pengaruh Konsentrasi Katalis MgO K2O Pada Transesterifikasi Minyak Biji Jarak (Ricinus Communis)”. Stannum : Jurnal Sains dan Terapan Kimia 6, no. 2 (October 31, 2024): 96–103. Accessed April 27, 2026. https://www.journal.ubb.ac.id/index.php/stannum/article/view/4692.