http://www.euronews.com/2017/12/08/view-visegrad-nations-protect-the-eu-it-s-time-to-say-thanks-
https://www.llri.lt/wp-content/uploads/2018/06/Labour-Migration_3.pdf
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/695321/An_inspection_of_exit_checks.pdf
https://www.la-croix.com/Monde/Miroslav-Lajcak-Ne-pas-penser-migration-comme-probleme-court-terme-2017-11-01-1200888652