Helwani, Z., Amraini, S. Z., Asmura, J., Siregar, T. N., Triwahyuni, V. E., & Abd , A. A. (2023). Palm Frond Waste as a Carbon Source in the Synthesis of CaO/Biochar Catalysts for the Biodiesel Production Process. Heca Journal of Applied Sciences, 1(1), 8–13. https://doi.org/10.60084/hjas.v1i1.9