Columbia subject headings:
Telecommunication policy--France--History--Congresses.
Telecommunication policy--Germany--History--Congresses.
Telecommunication policy--Italy--History--Congresses.
Telecommunication policy--United States--History--Congresses.
Harvard subject headings:
Telecommunication policy--France--History--Congresses.
Telecommunication policy--Germany--History--Congresses.
Telecommunication policy--Italy--History--Congresses.
Telecommunication policy--United States--History--Congresses.
Princeton subject headings:
Telecommunication policy--France--History--Congresses.
Telecommunication policy--History--Congresses.
Telecommunication--France--History--Congresses.
Telecommunication--History--Congresses.