(1999). United Nations conference on trade and development: Handbook of world mineral trade statistics 1991 - 1996. New York: United Nations.
Dyfyniad Arddull ChicagoUnited Nations Conference On Trade and Development: Handbook of World Mineral Trade Statistics 1991 - 1996. New York: United Nations, 1999.
Dyfyniad MLAUnited Nations Conference On Trade and Development: Handbook of World Mineral Trade Statistics 1991 - 1996. New York: United Nations, 1999.
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