Columbia subject headings:
Harvard subject headings:
Archives--Germany (East)--Congresses.
Germany (East). Ministerium für Staatssicherheit--Archival resources--Congresses.
Germany--History--Philosophy--Congresses.
Princeton subject headings:
Germany (East)--Politics and government--Congresses.
Germany (East). Ministerium für Staatssicherheit--Congresses.
Internal security--Germany (East)--History--Congresses.