Harvareza, Dina, Evrialiani Rosba, and Diana Susanti. “Validitas E-Book Berbasis Problem Based Learning Pada Materi Perubahan Lingkungan”. Bioscientist : Jurnal Ilmiah Biologi 11, no. 2 (December 30, 2023): 1084–1089. Accessed June 15, 2026. https://ojspanel.undikma.ac.id/index.php/bioscientist/article/view/8835.