Columbia subject headings:
Railroads--Freight--Rates--United States.
Railroads--United States--Rates.
Transportation, Automotive--Rates--United States.
Transportation, Automotive--United States--Rates.
United States. Interstate Commerce Commission.
Harvard subject headings:
Railroads--Freight--Rates--United States
Transportation, Automotive--Rates--United States.
United States. Interstate Commerce Commission.
Princeton subject headings:
Railroads--Freight--Rates--United States.
Transportation, Automotive--Rates--United States.
United States. Interstate Commerce Commission