Heller, H. (1977). International trade theory and empirical evidence/2nd ed. Prentice hall.
Chicago Style aipamenaHeller, H.Robert. International Trade Theory and Empirical Evidence/2nd Ed. New Delhi: Prentice hall, 1977.
MLA aipamenaHeller, H.Robert. International Trade Theory and Empirical Evidence/2nd Ed. Prentice hall, 1977.
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