http://www.consilium.europa.eu//media/32504/xt21004-ad01re02en18.pdf
http://blogs.lse.ac.uk/brexit/2017/07/06/the-1bn-bung-wont-protect-northern-ireland-from-the-pain-of-a-hard-brexit/
https://www.gov.uk/government/news/pms-open-letter-to-eu-citizens-in-the-uk
http://data.parliament.uk/writtenevidence/committeeevidence.svc/evidencedocument/treasury-committee/the-uks-economic-relationship-with-the-european-union/oral/72053.html