Pasaribu R. Pemberian Penguatan (Reinforcement) Terhadap Prestasi Belajar PAK Siswa. KERUGMA [Internet]. 2021 Oct. 31 [cited 2026 May 4];3(2):68-7. Available from: http://e-journal.sttiimedan.ac.id/index.php/kerugma/article/view/69