B. . Thomé, L. F. M. . Rezende, M. C. . Schveitzer, C. N. . Monteiro, and M. . Goldbaum, “Differences in the prevalence of risk factors for severe COVID-19 across São Paulo city regions: Differential risk factor prevalence for severe COVID-19 in São Paulo”, SciELO Preprints. Jul. 08, 2020. doi: 10.1590/1980-549720200087.