Typhoid fever dynamical model with cost-effective optimalcontrol. Journal of the Nigerian Society of Physical Sciences, [S. l.], v. 5, n. 4, p. 1579, 2023. DOI: 10.46481/jnsps.2023.1579. Disponível em: https://www.journal.nsps.org.ng/index.php/jnsps/article/view/1579.. Acesso em: 20 may. 2024.