Columbia subject headings:
Microwaves--United States.
Mobile communication systems--United States.
Radio--United States.
Telecommunication--United States.
Harvard subject headings:
Closed-circuit television--Law and legislation--United States--Digests.
Mobile radio stations--Law and legislation--United States--Digests.
Radiotelephone--Law and legislation--United States--Digests.
Telecommunication--Law and legislation--United States--Digests.
Princeton subject headings: