Columbia subject headings:
Church and state--Italy--Sicily--Congresses.
Papal legates--Italy--Sicily--Congresses.
Sicily (Italy)--Church history--Congresses.
Harvard subject headings:
Catholic Church--Italy--Sicily--History--Congresses.
Church and state--Italy--Sicily--Congresses.
Papal legates--Italy--Sicily--Congresses.
Sicily (Italy)--Church history--Congresses.
Princeton subject headings:
Church and state--Italy--Sicily--Congresses.
Papal legates--Italy--Sicily--Congresses.
Sicily (Italy)--Church history--Congresses.