Columbia subject headings:
Christian heresies--History--Middle Ages, 600-1500.
Christian heresies--Italy.
Harvard subject headings:
Christian heresies--Italy.
Christian heresies--Middle Ages, 600-1500.
Princeton subject headings:
Christian heresies--History--Middle Ages, 600-1500.
Christian heresies--Italy--History.
Italy--Church history--476-1400.