https://publications.parliament.uk/pa/ld5801/ldselect/ldeucom/4/4.pdf
https://ec.europa.eu/commission/sites/beta-political/files/slides_on_uk_technical_note_on_temporary_customs_arrangements.pdf
https://blogs.lse.ac.uk/brexit/2020/02/26/long-read-from-anglo-irish-to-british-irish-relations-whats-next/
http://www.oliverwyman.com/content/dam/oliver-wyman/v2/publications/2018/march/Oliver-Wyman_Clifford-Chance-The-Red-Tape-Cost-of-Brexit.pdf