Não informado. (2011). Annual Bulletin of Exports of Chemical Products. United Nations, Economic Commission for Europe.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Annual Bulletin of Exports of Chemical Products. New York: United Nations, Economic Commission for Europe, 2011.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Annual Bulletin of Exports of Chemical Products. United Nations, Economic Commission for Europe, 2011.
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