Columbia subject headings:
Harvard subject headings:
France--History--German occupation, 1940-1945.
Germany. Kriegsmarine--History.
Germany. Kriegsmarine--Submarine forces--History--20th century.
Navy-yards and naval stations--France--History--20th century.
Submarines (Ships)--Germany--History--20th century
Princeton subject headings:
France--History--German occupation, 1940-1945.
Germany. Kriegsmarine--History.
Germany. Kriegsmarine--Submarine forces--History--20th century.
Navy-yards and naval stations--France--History--20th century.
Submarines (Ships)--Germany--History--20th century.