http://www.epc.eu/documents/uploads/pub_7576_northernirelandandbrexit.pdf
https://ukandeu.ac.uk/trade-migration-and-brexit/
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/695321/An_inspection_of_exit_checks.pdf
https://blogs.lse.ac.uk/brexit/2019/10/09/northern-ireland-depends-on-the-eus-fluid-borders-for-survival/