Columbia subject headings:
Market surveys--United States.
Telecommunication switching systems equipment industry--United States.
Harvard subject headings:
Competition, International.
Market surveys--United States.
Telecommunication policy--United States
Telecommunication switching systems equipment industry--United States.
Telecommunication switching systems equipment industry.
Telephone switching systems, Electronic.
Princeton subject headings:
Market surveys--United States.
Telecommunication switching systems equipment industry--United States.