
http://www.niesr.ac.uk/sites/default/files/publications/Facing%20the%20Future%20Tackling%20post-Brexit%20Labour%20and%20skills%20NIESR.CIPD_.pdf

https://www.economiesuisse.ch/de/artikel/immerhin-zugang-zu-arbeitskraeften-aus-drittstaaten-gesichert

http://www.ilo.org/wcmsp5/groups/public/—dgreports/—dcomm/—publ/documents/publication/wcms_548950.pdf