Ortiz-Mena L. N. A. Jeffrey A. Frankel, Regional Trading Blocs in the World Economie System, Washington, D. C., Institute for International Economies, 1997, 364 p. PyG. 1999;6(2):543-546. Accedido octubre 13, 2026. http://politicaygobierno.cide.edu/index.php/pyg/article/view/457