4Viner J. The Customs Union Issue[M]. London:Steven, 1950.
5Ali M. Kutan, Taner M. European integration, productivity growth and real convergence[J]. EuropeanEconomic Review, 2007(51): 1370-1395.
6Tomas Maltby. European Union energy policy integration: A case of European Commission policy entrepreneurshipand increasing supranationalism[J]. Energy Policy, 2013(55):435-444.
7Maria Bejan. Trade agreements and international comovements: The case of NAFTA (North AmericanFree Trade Agreement[J]. Review of Economic Dynamics, 2011(14): 667-685.
8M. Henrekson, J. Torstensson, R. Torstensson. Growth effects of European integration[J]. EuropeanEconomic Review, 1997(41): 1537-1557.
