Columbia subject headings:
Harvard subject headings:
German reunification question (1949-1990)
Germany (East)--Boundaries--Germany (West)
Germany (East)--Politics and government.
Germany (East). Ministerium für Staatssicherheit.
Germany (West)--Boundaries--Germany (East)
Grenzkommission.
Internal security--Germany (East)
Princeton subject headings:
Germany (East)--Boundaries--Germany (West)
Germany (West)--Boundaries--Germany (East)
Grenzkommission (Germany)--History.