Neto, L. M. de A., A. L. M. Serrano, M. D. Wilbert, and P. A. P. de Britto. “Education and Income: A Comparative Study about Returns on Schooling in the State of Goias and the Federal District”. International Journal of Advances in Management and Economics, May 2018, https://managementjournal.info/index.php/IJAME/article/view/421.