Columbia subject headings:
Harvard subject headings:
Germany (East)--History--Congresses.
Germany (East)--Politics and government--Congresses.
Germany (East). Ministerium für Staatssicherheit--Congresses.
Internal security--Germany (East)--History--Congresses.
Secret service--Germany (East)--History--Congresses.
Princeton subject headings:
Germany (East)--Politics and government--Congresses.
Germany (East)--Social conditions--Congresses.
Germany (East). Ministerium für Staatssicherheit--Congresses.
Internal security--Germany (East)
Sozialistische Einheitspartei Deutschlands--Congresses.