Columbia subject headings:
Harvard subject headings:
Germany (East)--Politics and government--1989-1990--Sources.
Germany (East)--Politics and government.
Germany (East). Ministerium für Staatssicherheit--Sources.
Internal security--Germany (East)--History--Sources.
Secret service--Germany (East)--History--Sources.
Princeton subject headings:
Germany (East). Ministerium für Staatssicherheit
Internal security--Germany (East)