Improving Achievement Motivation for Mentally Disabled Students at School for Exceptional Children (SLB) YPAC Pangkalpinang. Berumpun: International Journal of Social, Politics, and Humanities, [S. l.], v. 2, n. 1, p. 15–24, 2019. DOI: 10.33019/berumpun.v2i1.15. Disponível em: https://www.berumpun.ubb.ac.id/index.php/BRP/article/view/8. Acesso em: 18 apr. 2026.