K. N. Varela, A. S. Fleck, C. R. Rhoden, L. B. Crippa, e R. M. E. Damiani, “Evaluation of air quality in Caxias do Sul/Brazil through bioassay and passive sampling of NO2 and O3 between September and November of 2014”, Sci. Electronic Arch, vol. 12, nº 1, p. 71–80, fev. 2019.