Heller, H. R. (1968). International trade theory and empirical evidence. Prentic- Hall.
Chicago-čujuhus (17. p.)Heller, H. Robert. International Trade Theory and Empirical Evidence. NewJersey: Prentic- Hall, 1968.
MLA-čujuhus (9. p.)Heller, H. Robert. International Trade Theory and Empirical Evidence. Prentic- Hall, 1968.
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