Columbia subject headings:
Harvard subject headings:
Espionage, East German--Congresses.
Germany (East). Ministerium für Staatssicherheit. Hauptverwaltung Aufklärung--History--Congresses.
Germany (East). Nationale Volksarmee
Intelligence service--Germany (East)--History--Congresses.
Princeton subject headings:
Espionage, East German--History--Congresses.
Espionage, East German--History.
Germany (East). Ministerium für Staatssicherheit. Hauptverwaltung Aufklärung--History--Congresses.
Germany (East). Ministerium für Staatssicherheit. Hauptverwaltung Aufklärung--History.
Intelligence service--Germany (East)--History--Congresses.
Intelligence service--Germany (East)--History.