http://www.independent.co.uk/news/uk/politics/article-127-brexit-stop-what-is-it-single-market-eu-eea-theresa-may-article-50-a7955806.html
https://publications.parliament.uk/pa/cm201719/cmselect/cmbeis/380/380.pdf
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/397079/Scotland_EnduringSettlement_acc.pdf