Columbia subject headings:
Poland--History--Occupation, 1939-1945--Chronology.
Poland--History--Occupation, 1939-1945.
World War, 1939-1945--Chronology.
World War, 1939-1945.
Harvard subject headings:
Poland--History--Occupation, 1939-1945
Poland--History--Occupation, 1939-1945--Chronology.
World War, 1939-1945--Chronology.
World War, 1939-1945--History.
Princeton subject headings:
Poland--History--Occupation, 1939-1945.
World War, 1939-1945--Campaigns--Poland.