Columbia subject headings:
Castles--Conservation and restoration--Italy--Campania--Congresses.
Castles--Conservation and restoration--Italy--Campania--Exhibitions.
Castles--Italy--Campania--Congresses.
Castles--Italy--Campania--Exhibitions.
Fortification--Italy--Campania--Congresses.
Fortification--Italy--Campania--Exhibitions.
Harvard subject headings:
Princeton subject headings:
Castles--Conservation and restoration--Italy--Campania--Congresses.
Castles--Conservation and restoration--Italy--Campania--Exhibitions.
Castles--Italy--Campania--Congresses.
Castles--Italy--Campania--Exhibitions.
Fortification--Italy--Campania--Congresses.
Fortification--Italy--Campania--Exhibitions.