https://www.gov.uk/guidance/status-of-eu-nationals-in-the-uk-what-you-need-to-know
https://blogs.lse.ac.uk/brexit/2020/02/26/long-read-from-anglo-irish-to-british-irish-relations-whats-next/
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/640485/Technical_note_on_Functionality_and_Protocol_7.pdf
https://www.unhcr.org/gcr/GCR_English.pdf