
https://english.elpais.com/international/2023-04-17/the-underground-bankers-of-the-people-smuggling-business.html

http://www.migrationobservatory.ox.ac.uk/resources/commentaries/brexodus-migration-and-uncertainty-after-the-eu-referendum/

http://www.bertelsmann-stiftung.de/fileadmin/files/Projekte/Migration_fair_gestalten/IB_PolicyBrief_Einwanderungsgesetz_082017_ENG.pdf