Columbia subject headings:
Atlantic Wall (France and Belgium)
World War, 1939-1945--Campaigns--Western Front.
Harvard subject headings:
Atlantic Wall (France and Belgium)
Fortification--Europe--History--20th century.
World War, 1939-1945--Artillery operations, German.
Princeton subject headings:
Atlantic Wall (France and Belgium)
Fortification--Europe.--History.--20th century.
World War, 1939-1945--Artillery operations, German.