C. L. Ejikeme, E. Abeh, M. B. Okofu, T. Ge, D. C. Ugo, and B. C. Agbata, “Dynamical Analysis of a Diphtheria Transmission Model with Epidemiological Data Fitting”, GPH-IJAS, vol. 6, no. 5, pp. 20-42, May 2023.