Dyfyniad APA

Helpman, E. (1990). Monopolistic competition in trade theory. International Finance Section, Princeton University.

Dyfyniad Arddull Chicago

Helpman, Elhanan. Monopolistic Competition in Trade Theory. Princeton, N.J: International Finance Section, Princeton University, 1990.

Dyfyniad MLA

Helpman, Elhanan. Monopolistic Competition in Trade Theory. International Finance Section, Princeton University, 1990.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.