https://www.euronews.com/2018/09/25/why-is-the-irish-border-issue-so-complex-euronews-answers
https://blogs.lse.ac.uk/brexit/2020/02/26/long-read-from-anglo-irish-to-british-irish-relations-whats-next/
https://www.gov.uk/government/news/david-davis-speech-to-the-suddeutsche-zeitung-economic-summit
https://www.instituteforgovernment.org.uk/sites/default/files/publications/5704%20IFG%20-%20Frictionless%20Trade%20Web.pdf