https://www.esri.ie/system/files/publications/RS158_0.pdf
http://www.assemblee-nationale.fr/14/pdf/rap-info/i4551.pdf
https://www.kcl.ac.uk/policy-institute/assets/uk-attitudes-to-immigration-1018742pub01-115.pdf
https://www.socialeurope.eu/deja-vu-home-office