https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef18025en.pdf
https://www.bruegel.org/sites/default/files/2024-02/PB%2004%202024_0.pdf
https://www.opendemocracy.net/uk/looking-at-lexit/guy-aitchison/borders-open-borders-or-no-borders?utm_source=Daily+Newsletter&utm_campaign=0a51e05bcc-DAILY_NEWSLETTER_MAILCHIMP&utm_medium=email&utm_term=0_717bc5d86d-0a51e05bcc-407405485
https://www.esri.ie/system/files/publications/RB202025.pdf