Columbia subject headings:
Carriers--United States.
Transportation, Automotive--Rates--United States.
Transportation, Automotive--United States--Rates.
Transportation--Rates--United States.
Transportation--United States--Rates.
Harvard subject headings:
Carriers--United States.
Transportation, Automotive--Rates--United States.
Transportation--Rates--United States
Transportation--Rates--United States.
Princeton subject headings:
Carriers--United States.
Transportation, Automotive--Rates--United States.
Transportation--Rates--United States.