http://www.cer.eu/sites/default/files/pb_ireland_brexit_6.7.17.pdf
https://bdi.eu/media/pressecenter/#/artikel/news/brexit-wirft-seine-schatten-voraus/
https://www.bloomberg.com/politics/articles/2017-04-26/brexit-risks-opening-pandora-s-box-of-trade-disputes-for-britain?cmpid=BBBXT042617_BIZ&utm_medium=email&utm_source=newsletter&utm_term=170426&utm_campaign=brexit
https://blogs.lse.ac.uk/brexit/2021/02/26/future-british-european-security-relations-are-a-matter-of-trust/