Columbia subject headings:
Employers' associations--European Union countries--Congresses.
Industrial relations--European Union countries--Congresses.
Labor unions--European Union countries--Congresses.
Harvard subject headings:
Employers' associations--European Union countries--Congresses.
Industrial relations--European Union countries--Congresses.
Labor unions--European Union countries--Congresses.
Princeton subject headings:
European Union countries--Economic conditions--20th century--Congresses.
Labor unions--European Union countries--Congresses.