Y. Mulyani, N. Nurhayati, and A. Awaluddin, “EFFECT OF ACIDITY, BASICITY, HETEROGENEOUS CaO/SILICA GEL CATALYST FROM BIOMASS WASTE ON BIODIESEL YIELD FROM CRUDE PALM OIL”, AK, vol. 11, no. 2, pp. 122–131, Dec. 2024.