SAKUR, S.; SARAGIH, S.; HUTAPEA, N. M. VALIDITAS BUKU AJAR MATA KULIAH GEOMETRI BERBASIS CAPAIAN PEMBELAJARAN. Jurnal Penelitian Ilmu Pendidikan Indonesia, [S. l.], v. 1, n. 2, p. 135–140, 2022. DOI: 10.31004/jpion.v1i2.29. Disponível em: https://jpion.org/index.php/jpi/article/view/29. Acesso em: 21 may. 2026.