Columbia subject headings:
Harvard subject headings:
Bologna (Italy)--History--1860-1945--Sources.
Bologna (Italy)--History--1945---Sources.
Italy--History--Allied occupation, 1943-1947--Sources.
World War, 1939-1945--Italy--Bologna--Sources.
Princeton subject headings:
Bologna (Italy : Province)--History--Sources.
Italy--History--Allied occupation, 1943-1947--Sources.