Chalis, G.A. and Ariani, yetti 2020. Pengaruh Model Problem Based Learning (PBL) Terhadap Hasil Belajar Pecahan di Sekolah Dasar. Jurnal Pendidikan Tambusai. 4, 3 (Nov. 2020), 2936–2944. DOI:https://doi.org/10.31004/jptam.v4i3.794.