Columbia subject headings:
Telecommunication--Rates--Law and legislation--United States--Mathematical models.
Telecommunication--Taxation--United States--Mathematical models.
Harvard subject headings:
Telecommunication--Rates--Law and legislation--United States--Mathematical models.
Telecommunication--Taxation--United States--Mathematical models.
Princeton subject headings:
Telecommunication--Rates--Law and legislation--United States--Mathematical models.
Telecommunication--Taxation--United States--Mathematical models.