Columbia subject headings:
Ocean liners--United States--History--19th century.
Ocean liners--United States--History--20th century.
Passenger ships--United States--History--19th century.
Passenger ships--United States--History--20th century.
Harvard subject headings:
Ocean liners--United States--History--19th century.
Ocean liners--United States--History--20th century.
Passenger ships--United States--History--19th century.
Passenger ships--United States--History--20th century.
Princeton subject headings:
Ocean liners--United States--History--19th century.
Ocean liners--United States--History--20th century.
Passenger ships--United States--History--19th century.
Passenger ships--United States--History--20th century.