Akbar, F.; Asyhar, A. H.; Lubab, A.; Hamid, A.; Hafiyusholeh, M.; Novitasari, D. C. R.; Arifin, A. Z.; Rozi, M. F. Vaccine Effectiveness Impact on the COVID-19 Dynamics Spread Outbreak Using Improved SEIR Mathematical Epidemic Model. Thai J Math 2024, 22, 485–502.