http://www.guengl.eu/news/article/eu-citizens-rights-and-status-of-north-of-ireland-must-be-prioritised-in-br
https://www.bloomberg.com/news/articles/2019-09-11/world-s-oldest-customs-union-and-u-k-reach-a-post-brexit-deal
https://bdi.eu/media/user_upload/20171005_Pressemitteilung_Brexit.pdf