Columbia subject headings:
Sicily (Italy)--Description and travel--Congresses.
Syracuse (Italy)--Description and travel--Congresses.
Visitors, Foreign--Italy--Sicily--Congresses.
Visitors, Foreign--Italy--Syracuse--Congresses.
Harvard subject headings:
Sicily (Italy)--Description and travel--Congresses.
Syracuse (Italy)--Description and travel--Congresses.
Visitors, Foreign--Italy--Sicily--Congresses.
Visitors, Foreign--Italy--Syracuse--Congresses.
Princeton subject headings:
Sicily (Italy)--Description and travel--Congresses.
Syracuse (Italy)--Description and travel--Congresses.
Visitors, Foreign--Italy--Sicily--Congresses.
Visitors, Foreign--Italy--Syracuse--Congresses.