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eurotreaties.com
The head of states of the EU member states (7 February 1992). "The Maastricht Treaty"(PDF). Treaty on the European Union. eurotreaties.com. Archived from the original(PDF) on 4 March 2006. Retrieved 9 July 2008.
The head of states of the EU member states (7 February 1992). "The Maastricht Treaty"(PDF). Treaty on the European Union. eurotreaties.com. Archived from the original(PDF) on 4 March 2006. Retrieved 9 July 2008.