https://www.politico.eu/article/the-brexit-referendum-10-years-on/
http://carnegieeurope.eu/2017/06/15/bringing-brexit-back-to-reality-pub-71262
https://researchbriefings.files.parliament.uk/documents/CBP-7212/CBP-7212.pdf
http://fedtrust.co.uk/brexitthe-conservative-centre-cannot-hold/