Columbia subject headings:
Harvard subject headings:
World War, 1939-1945--Germany--Juvenile literature.
World War, 1939-1945--Germany.
World War, 1939-1945--Secret service--Juvenile literature.
World War, 1939-1945--Secret service.
Princeton subject headings:
World War, 1939-1945--Germany.
World War, 1939-1945--Secret service.