
http://fedtrust.co.uk/views-from-the-federal-trust/free-movement-and-migration/

https://bdi.eu/media/user_upload/20171005_Pressemitteilung_Brexit.pdf

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/994125/FINAL_TIGRR_REPORT__1_.pdf