van Bergeijk, P. A. G. (2011). Gravity Model in International Trade: Advances and Applications. Cambridge University Press.
Παραπομπή Chicago Stylevan Bergeijk, Peter A. G. Gravity Model in International Trade: Advances and Applications. Cambridge University Press, 2011.
Παραπομπή MLAvan Bergeijk, Peter A. G. Gravity Model in International Trade: Advances and Applications. Cambridge University Press, 2011.
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