https://www.otto-brenner-stiftung.de/fileadmin/user_data/stiftung/Aktuelles/AH93/AH_93_Haller_Web.pdf
https://centreonconstitutionalchange.ac.uk/sites/default/files/2021-04/Union%20at%20the%20Crossroads.pdf
http://www.pewglobal.org/2017/06/15/post-brexit-europeans-more-favorable-toward-eu/?cmpid=BBBXT061617_BIZ&utm_medium=email&utm_source=newsletter&utm