Freitas, I. G. F., J. C. da S. Alves, E. V. C. Mariano, and G. L. Mariano. “Behavior of Nitrogen Dioxide on the Northeast Region of Brazil and Its Relationship With Meteorological Variables”. Ciência E Natura, vol. 40, Mar. 2018, pp. 32-38, doi:10.5902/2179460X30531.