Columbia subject headings:
Harvard subject headings:
Electronic intelligence--Germany (East)--History.
Germany (East). Nationale Volksarmee--Communication systems--History.
Germany (East). Nationale Volksarmee--History.
Radio, Military--Germany (East)--History.
Princeton subject headings:
Electronic intelligence--Germany (East)--History.
Germany (East). Nationale Volksarmee--Communication systems--History.
Germany (East). Nationale Volksarmee--History.
Radio, Military--Germany (East)--History.