Butar-Butar, Marintan. “PERANAN MODEL PROBLEM BASED LEARNING (PBL) PADA MATERI LIMIT FUNGSI ALJABAR KELAS XI SMA”. Jurnal Pendidikan Tambusai 2, no. 2 (June 24, 2018): 877–881. Accessed April 5, 2025. http://jptam.org/index.php/jptam/article/view/36.