Muliana et al. 2024. Pengaruh Penerapan Problem Based Learning (PBL) Terhadap Keterampilan Abad 21. Ar-Riyadhiyyat: Journal of Mathematics Education. 5, 1 (Jul. 2024), 22–30. DOI:https://doi.org/10.47766/arriyadhiyyat.v5i1.2900.