Tafrikan, Mohamad, Fatmawati, Windarto, and Chinwendu E. Madubueze. “Fractional Dynamics and Sensitivity Analysis of a Diphtheria Spread Model”. Statistics, Optimization & Information Computing (July 17, 2026). Accessed July 25, 2026. https://iapress.org/index.php/soic/article/view/3769.