PanjaitanHamonangan Panjaitan, Jabosar Ronggur, Della Yosia Situmorang, and Eykhel Sykhles Tarigan. 2026. “Production and Economic Evaluation of Biobased Detergent from Waste Cooking Oil”. Applied Science and Engineering Progress 19 (4):8098. https://doi.org/10.14416/j.asep.2026.04.002.