Columbia subject headings:
Customs administration--United States.
Information technology--United States.
U.S. Customs Service--Automation.
Harvard subject headings:
Customs administration--United States--Automation.
Customs administration--United States.
Information technology--United States
U.S. Customs Service--Automation.
Princeton subject headings:
Customs administration--United States.
Information technology--United States.
U.S. Customs Service--Automation.