Anangonó Rosero, G., and C. P. Naranjo Navas. “Bolívar Echeverría: On Existencialism”. HUMAN REVIEW. International Humanities Review / Revista Internacional De Humanidades, vol. 9, no. 2, Oct. 2020, pp. pp. 87-99, https://www.historicoeagora.net/revHUMAN/article/view/2431.