Nasution, Y., A. Susanta, dan Z. Zaili. “The Influence of Problem-Based Learning Model on students’ Ability Toward Understanding Mathematics Concepts in the Material of Linear Equations One Variable”. Math Didactic: Jurnal Pendidikan Matematika, Vol. 9, no. 2, Mei 2023, hlm. 235-46, doi:10.33654/math.v9i2.2110.