Columbia subject headings:
Harvard subject headings:
Freier Deutscher Gewerkschaftsbund
Germany (East)--Foreign relations.
Germany--Foreign relations--20th century.
Germany--Foreign relations--Spain.
Labor unions--Germany (East)--History--20th century.
Spain--Foreign relations--Germany.
Princeton subject headings:
Freier Deutscher Gewerkschaftsbund--History--20th century.
Germany (East)--Foreign relations--20th century.
Germany--Foreign relations--20th century.
Germany--Foreign relations--Spain.
Labor unions--Germany (East)--History--20th century.
Spain--Foreign relations--Germany.