HELLER H ROBERT. (1988). INTERNATIONAL TRADE: THEORY AND EMPRICAL EVIDENCE (2.). PRENTICE -HALL INTERNATIONAL, INC.
Lua i Stíl Chicago (17ú heag.)HELLER H ROBERT. INTERNATIONAL TRADE: THEORY AND EMPRICAL EVIDENCE. 2. NEW DELHI: PRENTICE -HALL INTERNATIONAL, INC, 1988.
Lua MLA (9ú heag.)HELLER H ROBERT. INTERNATIONAL TRADE: THEORY AND EMPRICAL EVIDENCE. 2. PRENTICE -HALL INTERNATIONAL, INC, 1988.
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