https://www.publications.parliament.uk/pa/ld201617/ldselect/ldeucom/116/116.pdf
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/638135/6.3703_DEXEU_Northern_Ireland_and_Ireland_INTERACTIVE.pdf
https://www.gov.uk/government/news/david-davis-opening-remarks-at-the-start-of-the-third-round-of-eu-exit-negotiations
https://publications.parliament.uk/pa/ld5801/ldselect/ldeucom/4/4.pdf