Monteiro, V. B., and P. U. de C. Castelar. “Private Funding in Campaigns: An Analysis of Electoral Competition Indexes in the 2014 and 2018 Proportional Elections”. Economia & Região, vol. 10, no. 2, July 2022, pp. 115-37, doi:10.5433/2317-627X.2022v10n2p115.