T.-D. Dao, V.-H. Kieu, H.-N. Kieu Thi, C.-N. Nguyen, and T.-H. Dinh Thi, “Some notes on the dynamic behavior of COVID-19 epidemic disease governed by modified SEIR epidemic model with saturated treatment function”, HPU2. Nat. Sci. Tech, vol. 1, no. 2, pp. 3–23, Dec. 2022.