Helpman, E., & Krugman, P. R. (1985). Market structure and foreign trade: Increasing returns, imperfect competition, and the international economy. MIT Press.
Citação norma ChicagoHelpman, Elhanan, and Paul R. Krugman. Market Structure and Foreign Trade: Increasing Returns, Imperfect Competition, and the International Economy. Cambridge, Mass.: MIT Press, 1985.
Citação norma MLAHelpman, Elhanan, and Paul R. Krugman. Market Structure and Foreign Trade: Increasing Returns, Imperfect Competition, and the International Economy. MIT Press, 1985.
Nota: a formatação da citação pode não corresponder 100% ao definido pela respectiva norma.