Ogunmodimu, M.O., T.T. Yusuf, and O. Olotu. “Sensitivity and Stability Analyses of COVID-19 Model With Waning Immunity and Relapse: A Case Study of Nigeria”. International Journal of Mathematical Analysis and Modelling 8, no. 1 (July 23, 2025). Accessed September 12, 2026. https://journal.tnsmb.org/index.php/ijmam/article/view/220.