Columbia subject headings:
Castles--Conservation and restoration--Congresses.
Castles--Liechtenstein--Catalogs.
Castles--Switzerland--Catalogs.
Castles--Switzerland--History--Congresses.
Nobility--Switzerland--History--Congresses.
Palaces--Switzerland--History--Congresses.
Harvard subject headings:
Castles--Conservation and restoration--Congresses.
Castles--Switzerland--History--Catalogs--Congresses.
Castles--Switzerland--History--Congresses.
Nobility--Switzerland--History--Congresses.
Palaces--Switzerland--History--Congresses.
Princeton subject headings:
Castles--Conservation and restoration--Congresses.
Castles--Liechtenstein--Catalogs.
Castles--Switzerland--Catalogs.
Castles--Switzerland--History--Congresses.
Nobility--Switzerland--History--Congresses.
Palaces--Switzerland--History--Congresses.