HARAHAP, Nia Helmita; LUBIS, Mara Samin. Development of Student Worksheets (LKPD) on Integer Topics to Improve Seventh-Grade Students’ Mathematical Problem Solving Abilities at SMP Negeri 3 Halongonan. Mathline : Jurnal Matematika dan Pendidikan Matematika, [S. l.], v. 11, n. 1, p. 91–106, 2026. DOI: 10.31943/mathline.v11i1.1105. Disponível em: http://mathline.unwir.ac.id/index.php/Mathline/article/view/1105. Acesso em: 25 feb. 2026.