UDOFIA *, E. .; UWAKWE †, J. .; THOMAS, H. . Optimal control and sensitivity analysis of age-structured mathematical model of Diphtheria infection. International Journal of Mathematical Analysis and Modelling, [S. l.], v. 7, n. 1, 2024. Disponível em: https://tnsmb.org/journal/index.php/ijmam/article/view/139. Acesso em: 28 jul. 2026.