
https://policyexchange.org.uk/wp-content/uploads/2017/06/Defying-Gravity-A-critique-of-estimates-of-the-economic-impact-of-Brexit.pdf

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

http://fedtrust.co.uk/our-work-on-europe/brexit-heading-to-a-deal-or-no-deal-while-uk-politics-implodes/