https://blogs.lse.ac.uk/brexit/2019/08/12/boris-johnsons-real-agenda-the-singapore-scenario/
https://institute.global/news/customs-and-exiting-european-union
http://www.failteireland.ie/FailteIreland/media/WebsiteStructure/Documents/Brexit/Exchange-rate-impacts-Update-19th-June-2018.pdf?ext=.pdf
https://blogs.lse.ac.uk/brexit/2021/01/11/article-16-of-the-ireland-northern-ireland-protocol-offers-no-quick-fix/