Columbia subject headings:
Poland--History--Occupation, 1939-1945.
World War, 1939-1945--Atrocities.
World War, 1939-1945--Poland.
World War, 1939-1945--Prisoners and prisons, German.
Harvard subject headings:
Poland--History--Occupation, 1939-1945
World War, 1939-1945--Atrocities.
World War, 1939-1945--Poland.
World War, 1939-1945--Prisoners and prisons, German.
Princeton subject headings:
Poland--History--Occupation, 1939-1945.
World War, 1939-1945--Atrocities.
World War, 1939-1945--Poland.
World War, 1939-1945--Prisoners and prisons, German.