Columbia subject headings:
Harvard subject headings:
Normans--Italy--Sicily--Congresses.
Roger II, King of Sicily, 1095-1154--Congresses.
Sicily (Italy)--History--Roger II, 1105-1154--Congresses.
Princeton subject headings:
Normans--Italy--Sicily--Congresses.
Roger II, King of Sicily, 1095-1154--Congresses.
Sicily (Italy)--History--Roger II, 1105-1154--Congresses.