Columbia subject headings:
Harvard subject headings:
Border patrols--Germany (East)--History.
Border security--Germany (East)--History.
Germany (East). Deutsche Grenzpolizei--History.
Germany (East). Nationale Volksarmee. Kommando Grenze--History.
Princeton subject headings:
Border patrols--Germany (East)--History.
Germany (East). Deutsche Grenzpolizei--History.
Germany (East). Nationale Volksarmee. Kommando Grenze--History.