Columbia subject headings:
Catholic Church--Italy--Ravenna--History.
Clement III, Antipope, approximately 1025-1100.
Ravenna (Italy)--Church history.
Harvard subject headings:
Catholic Church--Italy--Ravenna--History.
Clement III, Antipope, approximately 1025-1100.
Ravenna (Italy)--Church history.
Princeton subject headings:
Catholic Church--Italy--Ravenna--History.
Clement III, Antipope, approximately 1025-1100.
Ravenna (Italy)--Church history.