Natewong P, Prasongthum N, Murakami Y, Tanid H, Asami K. Effect of Addition of CaO and ZrO2 on the Performance of MgO/AC Catalyst for the Synthesis of New Bio-Diesel (HiBD) from Waste Cooking Oil. ASRJETS-Journal. 2016;24(1):76-89. Accessed September 12, 2025. https://www.asrjetsjournal.org/American_Scientific_Journal/article/view/2032