N. A. Mohamad Zainizam and H. . Mohd Safuan, “A SIR Model Assumption for the Spread of COVID-19 with the Effects of Vaccination”, EKST, vol. 2, no. 1, pp. 231–240, Aug. 2022, Accessed: Apr. 08, 2026. [Online]. Available: https://penerbit.uthm.edu.my/periodicals/index.php/ekst/article/view/5437