
https://www.instituteforgovernment.org.uk/sites/default/files/publications/voting-on-brexit-report-final.pdf

https://www.gov.uk/government/news/david-davis-opening-remarks-at-the-start-of-the-third-round-of-eu-exit-negotiations

http://docs.dpaq.de/10395-0216-euco-conclusions.pdf