http://blogs.lse.ac.uk/politicsandpolicy/john-mills-ge2017/
http://visual.ons.gov.uk/trading-places-uk-goods-trade-with-eu-partners/
http://fedtrust.co.uk/views-from-the-federal-trust/free-movement-and-migration/
https://www.politico.eu/article/time-for-brexit-reckoning-uk-eu-relationship/