Columbia subject headings:
Fortification--Italy--Exhibitions.
Military architecture--Conservation and restoration--Italy--Exhibitions.
Military architecture--Italy--History--Exhibitions.
Harvard subject headings:
Fortification--Italy--Exhibitions.
Military architecture--Conservation and restoration--Italy--Exhibitions.
Military architecture--Italy--History--Exhibitions.
Princeton subject headings:
Fortification--Italy--Exhibitions.
Military architecture--Conservation and restoration--Italy--Exhibitions.
Military architecture--Italy--History--Exhibitions.