https://publications.parliament.uk/pa/cm201719/cmselect/cmhaff/421/421.pdf
https://www.opendemocracy.net/uk/peter-geoghegan/growing-up-on-border-on-brexit-s-irish-problem?utm_source=Daily+Newsletter&utm_campaign=b906170335-DAILY_NEWSLETTER_MAILCHIMP&utm_medium=email&utm_term=0_717bc5d86d-b906170335-407405485
http://www.cesifo-group.de/ifoHome/publications/working-papers/CESifoWP/CESifoWPdetails?wp_num=6438&CESifoWP.search=+
https://ec.europa.eu/commission/sites/beta-political/files/slides_on_uk_technical_note_on_temporary_customs_arrangements.pdf