Closa, C. (2015). "Looking ahead: pathways of future constitutional evolution of the EU". Directorate General for Internal policies, Citizens´ rights and constitutional affairs.

Abstract: The effects of the economic and fiscal crisis and the institutional instruments created to deal with it have led several actors (from governments and EU bodies to scholars) to propose different EU reforms. Several options exist to accommodate future constitutional development which, in some cases, may require Treaty revision. In this case, future constitutional evolution faces the challenge that the very stringent EU revision requirement (i.e. unanimity) poses. Other available options do not seem totally satisfactory.