International Monetary Fund. Real Sector Division & ebrary, Inc. (1993). A Guide to Direction of trade statistics. International Monetary Fund.
Chicago-viite (17. p.)International Monetary Fund. Real Sector Division ja Inc ebrary. A Guide to Direction of Trade Statistics. Washington, D.C.: International Monetary Fund, 1993.
MLA-viite (9. p.)International Monetary Fund. Real Sector Division ja Inc ebrary. A Guide to Direction of Trade Statistics. International Monetary Fund, 1993.
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