Mathematical Modeling with Two Strains to Investigate Evolution of COVID-19 from Computational and Theoretical Perspectives. European Journal of Pure and Applied Mathematics, Maryland, USA, v. 18, n. 2, p. 6001, 2025. DOI: 10.29020/nybg.ejpam.v18i2.6001. Disponível em: https://www.ejpam.com/index.php/ejpam/article/view/6001. Acesso em: 5 dec. 2025.