https://www.politico.eu/article/the-uk-failed-10-year-bid-to-fix-the-brexit-border-northern-ireland/
https://ec.europa.eu/commission/sites/beta-political/files/joint_table_citizens_rights_-_third_round.pdf
http://www.cer.org.uk/sites/default/files/insight_JS_9.5.17.pdf
https://ec.europa.eu/commission/sites/beta-political/files/seminar-20200114-lpf_en.pdf