Aliwarga, Lienda, Setyo Widodo, Novika Suwardana, Hanna Darmawan, Khoiruddin Khoiruddin, and I Gede Wenten. 2019. “Impurity Removal of Waste Cooking Oil Using Hydrophobic Polypropylene Hollow Fiber Membrane”. Journal of Engineering and Technological Sciences 51 (2):216-30. https://doi.org/10.5614/j.eng.technol.sci.2019.51.2.5.