Fonseca, Felipe J. “The Impact of the Campaign Spending on the 2006 Presidential Election in Mexico: An Approximation”. Estudios Económicos de El Colegio de México 37, no. 2 (July 13, 2022): 199–232. Accessed May 13, 2025. https://estudioseconomicos.colmex.mx/index.php/economicos/article/view/430.