Ardan, Syafira, Ananda Putra, Latisma DJ, Rita Sundari, Sri Benti Etika, and Umar Kalmar Nizar. 2019. “THE STUDY OF REUSED SILICA-TITANIA CATALYST ON BIODIESEL PRODUCTION IN VARIOUS REACTION TIMES”. International Journal of Advances in Scientific Research and Engineering (IJASRE), ISSN:2454-8006, DOI: 10.31695/IJASRE 5 (8):133-41. https://doi.org/10.31695/IJASRE.2019.33458.