Columbia subject headings:
Harvard subject headings:
Germany (East)--Foreign relations--Germany (West)
Germany (West)--Foreign relations--Germany (East)
Political prisoners--Germany (East)--History.
Ransom--Germany (East)--History.
Princeton subject headings:
Germany (East)--Foreign relations--Germany (West)
Germany (West)--Foreign relations--Germany (East)
Political prisoners--Germany (East)--History.
Ransom--Germany (East)--History.