Columbia subject headings:
Harvard subject headings:
Guelfs and Ghibellines
Italy--History--1268-1492--Sources.
Italy--History--1268-1492.
Italy--History--Germanic rule, 962-1268--Sources.
Italy--History--Germanic rule, 962-1268.
Princeton subject headings:
Guelfs and Ghibellines.
Italy--History--1268-1492.
Italy--History--Germanic rule, 962-1268.