http://fedtrust.co.uk/views-from-the-federal-trust/free-movement-and-migration/
https://www.ips-journal.eu/topics/democracy-and-society/eastern-europe-needs-a-new-immigration-narrative-7412/
https://publications.parliament.uk/pa/cm201719/cmselect/cmcumeds/365/365.pdf
https://www.politico.eu/article/the-brexit-referendum-10-years-on/