Columbia subject headings:
Historic gardens--Conservation and restoration--Europe--Congresses.
Historic gardens--Conservation and restoration--Italy--Congresses.
Historic gardens--Europe--Congresses.
Historic gardens--Italy--Congresses.
Harvard subject headings:
Historic gardens--Conservation and restoration--Europe--Congresses.
Historic gardens--Conservation and restoration--Italy--Congresses.
Historic gardens--Europe--Congresses.
Historic gardens--Italy--Congresses.
Princeton subject headings:
Historic gardens--Conservation and restoration--Europe--Congresses.
Historic gardens--Conservation and restoration--Italy--Congresses.
Historic gardens--Europe--Congresses.
Historic gardens--Italy--Congresses.