HAQ, I. U.; ALI, N.; NISAR, K. S. An optimal control strategy and Grünwald-Letnikov finite-difference numerical scheme for the fractional-order COVID-19 model. Mathematical Modelling and Numerical Simulation with Applications, [S. l.], v. 2, n. 2, p. 108–116, 2022. DOI: 10.53391/mmnsa.2022.009. Disponível em: https://mmnsa.org/index.php/mmnsa/article/view/27. Acesso em: 24 apr. 2024.