Wijaya, Karna, Idra Herlina, Wega Trisunaryanti, Nuryono, and Sahat Simbolon. 2018. “Biodiesel Preparation from Oil Fraction of Crude Pond Palm Oil through ZrO2 SO3H+-Catalyzed Esterification Followed by KOH-Catalyzed Transesterification”. Asian Journal of Chemistry 30 (4):724-30. https://doi.org/10.14233/ajchem.2018.19770.