http://www.ecb.europa.eu/pub/pdf/other/ebart201703_01.en.pdf
https://www.bloomberg.com/news/articles/2019-09-11/world-s-oldest-customs-union-and-u-k-reach-a-post-brexit-deal
https://www.cbi.org.uk/media/4112/the-red-tape-challenge-final.pdf
https://www.lobbycontrol.de/wp-content/uploads/gaslobby-studie-lobbycontrol.pdf