Meunier, S. (2000). What Single Voice? European Institutions and EU-U.S. Trade Negotiations. International Organization, Vol. 54, No. 1 (Winter, 2000), pp. 103-135
http://www.jstor.org/stable/pdfplus/2601319.pdf. Accessed March 12, 2010  

"Let's unite. And the world will listen to us" was an ad campaign used to mobilize the pro-European camp in France during the 1992 referendum on the Maastricht Treaty on European Union.1 This slogan summarizes well one of the central rationales for trade integration: by pooling together their resources and creating a large market attractive to foreign trading interests, the constituent members of the European Union (EU)2 can obtain greater international leverage than they would by acting individually. From the creation of the European Community (EC) in 1957, member countries accepted the principle of a single external voice in trade and therefore transferred their sovereignty over trade policy to the supranational level.Â