Sarif, Yeni, Noor Fadiawati, and M. Mahfudz Fauzi Syamsuri. “The Effectiveness Of Waste Cooking Oil Recycling Project-Based Learning To Improve Students’ High Order Thingking Skills”. IJCER (International Journal of Chemistry Education Research) 3, no. 1 (July 9, 2019): 29–34. Accessed May 18, 2024. https://jurnal.uii.ac.id/IJCER/article/view/12749.