Columbia subject headings:
France--History--1914-1940.
Germany--History--1871-1918.
World War, 1914-1918--France.
World War, 1914-1918--Germany.
Harvard subject headings:
France--History--German occupation, 1914-1918.
World War, 1914-1918--France
Princeton subject headings:
France--History--German occupation, 1914-1918.
World War, 1914-1918--France.