Não informado. (2011). Annual Bulletin of Exports of Chemical Products. United Nations, Economic Commission for Europe.
Citação do estilo Chicago (17ª ed.)Não informado. Annual Bulletin of Exports of Chemical Products. New York: United Nations, Economic Commission for Europe, 2011.
Citação MLA (8ª ed.)Não informado. Annual Bulletin of Exports of Chemical Products. United Nations, Economic Commission for Europe, 2011.
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