Columbia subject headings:
Harvard subject headings:
Europe--Foreign relations--Great Britain.
European Union--Great Britain.
France--Foreign relations--Great Britain.
Germany--Foreign relations--Great Britain.
Great Britain--Foreign relations--Europe.
Great Britain--Foreign relations--France.
Great Britain--Foreign relations--Germany.
International relations--History--20th century
International relations--History--21st century
Princeton subject headings:
European Union countries--Foreign relations--Great Britain.
European Union--Great Britain.
France--Foreign relations--Germany.
Germany--Foreign relations--France.
Great Britain--Foreign relations--European Union countries.
Referendum--Great Britain--History--21st century.