Columbia subject headings:
Rivers--Great Britain.
Rivers--United States.
Water--Law and legislation--Great Britain.
Water--Law and legislation--United States.
Harvard subject headings:
Harbors--United States
Inland navigation--Law and legislation--Great Britain.
Inland navigation--Law and legislation--United States.
Rivers--United States
Princeton subject headings:
Harbors--United States.
Rivers--United States.
Water--Law and legislation--Great Britain.
Water--Law and legislation--United States.