Columbia subject headings:
Harvard subject headings:
Military topography--Europe--Maps.
World War, 1914-1918--Campaigns--Western Front--Maps.
World War, 1914-1918--Cartography--History.
World War, 1914-1918--Trench warfare--Maps.
Princeton subject headings:
World War, 1914-1918--Campaigns--France--Maps.
World War, 1914-1918--French warfare--Maps.