https://www.gov.uk/government/news/joint-article-a-deep-and-special-partnership
https://docs.iza.org/dp16728.pdf
https://centreforbrexitpolicy.org.uk/wp-content/uploads/2020/07/REPLACING-THE-WITHDRAWAL-AGREEMENT-How-to-ensure-the-UK-takes-back-control-on-exiting-the-transition-period-12-July-20.pdf
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/725288/The_future_relationship_between_the_United_Kingdom_and_the_European_Union.pdf