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↑Klodt, Henning (2003), Pethig, Rüdiger; Rauscher, Michael (eds.), "Prospective Trade Effects of Eastern EU Enlargement", Challenges to the World Economy, Berlin, Heidelberg: Springer, p. 110, doi:10.1007/978-3-642-19018-6_10, ISBN978-3-642-19018-6