Dyfyniad APA

Helpman,Elhanan. (1978). A theory of international trade under uncertainty. Academic Press.

Dyfyniad Arddull Chicago

Helpman,Elhanan. A Theory of International Trade Under Uncertainty. New York: Academic Press, 1978.

Dyfyniad MLA

Helpman,Elhanan. A Theory of International Trade Under Uncertainty. Academic Press, 1978.

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