Siregar H. PENINGKATAN KOMPETENSI GURU MENERAPKAN MODEL PEMBELAJARAN PROBLEM BASED LEARNING (PBL) MELALUI WORKSHOP BAGI GURU MATA PELAJARAN KELAS IX DI UPT SMP NEGERI 20 MEDAN. jetl [Internet]. 2020 Dec. 6 [cited 2025 Oct. 12];1(3):41-5. Available from: https://pusdikra-publishing.com/index.php/jetl/article/view/47