Allen, Osvaldo, Ava Brown, and Ersong Wang. “Socioeconomic Disparities in the Effects of Pollution on Spread of Covid-19: Evidence from US Counties”. Journal of Economics and Behavioral Studies 12, no. 6(J) (February 9, 2021): 33-42. Accessed April 22, 2021. https://ojs.amhinternational.com/index.php/jebs/article/view/3131.