Sierra Rincón, Olga, and Yamile Vargas Noy. “Corruption in Companies and Vat Tax Evasion in Colombia: An Alternative Method of Measurement”. Revista CIFE: Lecturas De Economía Social, vol. 17, no. 26, July 2016, pp. 37-74, https://doi.org/10.15332/s0124-3551.2015.0026.02.