Mathematical Model of the Effect of Out-of-School Children on the Development of Northern Nigeria. International Journal of Development Mathematics (IJDM), [S. l.], v. 3, n. 3, p. 288–306, 2026. DOI: 10.62054/ijdm/0303.14. Disponível em: https://ijdm.org.ng/index.php/Journals/article/view/392.. Acesso em: 9 sep. 2026.