Columbia subject headings:
Sicily (Italy)--Foreign relations--Congresses.
Sicily (Italy)--Politics and government--To 1282--Congresses.
Harvard subject headings:
Sicily (Italy)--Foreign relations--Congresses.
Sicily (Italy)--Politics and government--To 1282--Congresses.
Princeton subject headings:
Sicily (Italy)--Foreign relations--Congresses.
Sicily (Italy)--History--To 800--Congresses.
Sicily (Italy)--Politics and government--To 1282--Congresses.