Correa, Martha, et al. “NO2 Correlation Using Sentinel-5P Images and on-Site Measurements During the Evolution of COVID-19 and Its Influence in the Metropolitan District of Quito, Ecuador”. International Journal on Advanced Science, Engineering and Information Technology, vol. 12, no. 3, May 2022, pp. 1105-12, doi:10.18517/ijaseit.12.3.14740.