
http://www.cobcoe.eu/files/cobcoe-brexit-report-september-2017-e-Y4G2st.pdf

https://www.politico.eu/article/the-uk-failed-10-year-bid-to-fix-the-brexit-border-northern-ireland/

https://www.gov.uk/government/news/david-davis-speech-to-the-suddeutsche-zeitung-economic-summit