Columbia subject headings:
Harvard subject headings:
Belgium--History--German occupation, 1940-1945.
World War, 1939-1945--Belgium--Refugees.
World War, 1939-1945--Belgium.
Princeton subject headings:
Belgium--History--German occupation, 1940-1945.
World War, 1939-1945--Belgium.
World War, 1939-1945--Refugees--Belgium.