USRI, W. R.; FITRIA, Y. Achievement of Student Learning Competencies Using Problem Based E-Book in Primary School . Tunas: Jurnal Pendidikan Guru Sekolah Dasar, [S. l.], v. 9, n. 1, p. 15–23, 2023. DOI: 10.33084/tunas.v9i1.6406. Disponível em: https://journal.umpr.ac.id/index.php/tunas/article/view/6406. Acesso em: 10 may. 2024.