Columbia subject headings:
Aquatic pests--Control--Law and legislation--United States.
Ballast water--United States.
Marine engineering--United States.
Shipbuilding industry--Law and legislation--United States.
Harvard subject headings:
Aquatic pests--Control--Law and legislation--United States.
Ballast water--United States.
Marine engineering--United States.
Shipbuilding industry--Law and legislation--United States.
Princeton subject headings: