Columbia subject headings:
Harvard subject headings:
Deutsche Bundespost Telekom--History.
Deutsche Telekom--History.
Telecommunication--Germany (East)--History.
Telecommunication--Germany (West)--History.
Telecommunication--Germany--History.
Telecommunication--Mergers--Germany--History.
Princeton subject headings:
Deutsche Bundespost Telekom--History.
Deutsche Telekom--History.
Telecommunication--Germany (East)--History.
Telecommunication--Germany (West)--History.
Telecommunication--Mergers--Germany--History.