Documented and Undocumented Immigrant Workers in the UK : Changing Environments and Shifting Strategies - Düvell, Franck (. Illegal immigration in Europe. - 1. publ.. - Houndmills [u.a.] : Palgrave Macmillan, 2006. - XI, 271 S.. - ISBN 1-4039-9741-1, 2006)