Purba, D. A., A. S. Nasution, and N. Andriani. “Improving Student Learning Outcomes With Problem Based Learning in Islamic Learning at SD Negeri 102112 Sipispis”. Jurnal Pendidikan Profesi Guru, vol. 1, no. 1, Feb. 2023, pp. 210-7, https://journal.ar-raniry.ac.id/ppg/article/view/6677.