Harahap, Army Fahita, and Nirwana Anas. 2026. “Pengaruh Model Project Based Learning (PjBL) Terhadap Keterampilan Proses Sains Siswa SD Pada Materi Sistem Pencernaan Manusia”. Walada: Journal of Primary Education 5 (2):1803-14. https://doi.org/10.61798/wjpe.v5i2.700.