IQBAL, M. N. COVID-19 Pandemic: The Omicron Variant and Natural Immunity. International Journal of Molecular Microbiology, [S. l.], v. 4, n. 3, p. 49–51, 2021. Disponível em: https://psmjournals.org/index.php/ijmm/article/view/696. Acesso em: 18 می. 2024.