Columbia subject headings:
Harvard subject headings:
Ardennes (France)--History.
France--History--German occupation, 1914-1918.
World War, 1914-1918--France--Ardennes--Posters.
Princeton subject headings:
Ardennes (France)--History.
France--History--German occupation, 1914-1918.
World War, 1914-1918--France--Ardennes--Posters.