https://infacts.org/fight-brexit-including-changing-mind/
https://ec.europa.eu/commission/publications/position-paper-transmitted-eu27-issues-relating-functioning-union-institutions-agencies-and-bodies_en
https://www.instituteforgovernment.org.uk/sites/default/files/publications/IfG_Brexit_customs_WEB.pdf
https://www.tandfonline.com/doi/epdf/10.1080/01402382.2023.2168945?needAccess=true&role=button