Columbia subject headings:
Harvard subject headings:
Foreign workers--European Union countries--Congresses.
Freedom of movement--European Union countries--Congresses.
Labor mobility--European Union countries--Congresses.
Princeton subject headings:
European Union countries--Emigration and immigration--Congresses.
Foreign workers--European Union countries--Congresses.
Free choice of employment--European Union countries--Congresses.
Freedom of movement--European Union countries--Congresses.
Labor laws and legislation--European Union countries--Congresses.