Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Federalisation of the European Union:

This text is part of the article's lead section, so referencing it may be optional. Please see WP:CITELEAD for more information.

"

Since the 1950s, European integration has seen the development of a supranational system of governance, as its institutions move further from the concept of simple intergovernmentalism and more towards a federalised system.[citation needed] However, with the Maastricht Treaty of 1992, new intergovernmental elements have been introduced alongside the more federal systems, making it more difficult to define the EU. The European Union, which operates through a hybrid system of intergovernmentalism and supranationalism, is not officially a federation or even a confederation – though most contemporary scholars of federalism view it as a federal system.[1]