Sanusi, Muhammad Syakir, et al. “Characterization of Raw Kapok Fiber As Filtration Medium For  Biodiesel Plant Waste Oil”. Research Progress in Mechanical and Manufacturing Engineering, vol. 5, no. 1, Oct. 2024, pp. 410-8, https://publisher.uthm.edu.my/periodicals/index.php/rpmme/article/view/17006.