Columbia subject headings:
Harvard subject headings:
Cold War
Espionage, East German.
Espionage, West German--Germany (East)--History--20th century.
Intelligence service--Germany (West)--History--20th century.
Secret service--Germany (West)--History--20th century.
Princeton subject headings:
Cold War.
Espionage, East German.
Espionage, West German--Germany (East)--History--20th century.
Intelligence service--Germany (West)--History--20th century.
Secret service--Germany (West)--History--20th century.