Columbia subject headings:
Export marketing--United States--Data processing.
Exports--United States--Data processing.
Foreign trade regulation--United States--Data processing.
U.S. Customs Service--Databases.
Harvard subject headings:
Export marketing--United States--Data processing.
Exports--United States--Data processing.
Foreign trade regulation--United States--Data processing.
U.S. Customs Service--Databases.
Princeton subject headings: