РЕВАЛСКИ, Ю.; САВОВ, М. Recent developments in modelling COVID-19 pandemic. Mathematics and Education in Mathematics, [S. l.], v. 50, p. 345–346, 2021. Disponível em: https://smb.math.bas.bg/mem/index.php/memjournal/article/view/42. Acesso em: 5 oct. 2026.