I MADE PERTA. OPTIMALISASI PELAKSANAAN MODEL PEMBELAJARAN PROBLEM SOLVING UNTUK MENINGKATKAN PRESTASI BELAJAR IPS SISWA. Jurnal Bakti Saraswati (JBS), [S. l.], v. 9, n. 2, 2020. Disponível em: https://e-journal.unmas.ac.id/index.php/baktisaraswati/article/view/1117. Acesso em: 18 may. 2025.