Columbia subject headings:
Europe--Economic integration--History.
European Union countries--History.
European Union--History.
European communities--History.
European federation--History.
Harvard subject headings:
Europe--Economic integration--History.
European Union countries--History.
European Union--History.
European communities--History.
European federation--History
Princeton subject headings:
Europe--Economic integration--History.
European Union countries--History.
European Union--History.
European communities--History.
European federation--History.