Columbia subject headings:
Air defenses--Germany (East)
Germany. Heer--Communication systems.
Military art and science--Germany--History--20th century.
Radio, Military--Germany (East)
Wireless communication systems--Military aspects--Germany (East)
Harvard subject headings:
Air defenses--Germany (East)
Germany. Heer--Communication systems.
Military art and science--Germany--History--20th century.
Radio, Military--Germany (East)
Wireless communication systems--Military aspects--Germany (East)
Princeton subject headings:
Air defenses--Germany (East).
Germany. Heer--Communication systems.
Military art and science--Germany--History--20th century.
Radio, Military--Germany (East).
Wireless communication systems--Military aspects--Germany (East).