Kartamiharja, Momo Rosbiono, Wahyu Sopandi, and Dini Anggraeni. 2020. “Implementation of Problem-Based Learning (PBL) Approach in Chemistry Instructional With Context of Tofu Liquid Waste Treatment”. International Journal of Learning, Teaching and Educational Research 19 (5):47-77. https://ijlter.net/index.php/ijlter/article/view/331.