Columbia subject headings:
Harvard subject headings:
Navies--History--19th century.
Navies--History--20th century.
Submarine warfare--History--19th century.
Submarine warfare--History--20th century.
Torpedoes--History--19th century.
Torpedoes--History--20th century.
Princeton subject headings:
Navies--History--19th century.
Navies--History--20th century.
Submarine warfare--History--19th century.
Submarine warfare--History--20th century.
Torpedoes--History--19th century.
Torpedoes--History--20th century.