Rudy Purwanto, S.Si, M.Pd., Dra Nurhayati, Rizki Uni Utami, S.Pd, Gr. “SB2 COLLA METHOD : APPLICATION OF PROBLEM BASED LEARNING MODEL TO IMPROVE STUDENT LITERATURE”. Jurnal Pendidikan Dompet Dhuafa, Vol. 12, no. 01, Aug. 2022, pp. 29-36, https://ojs.pendidikandd.org/index.php/JPD/article/view/284.