Columbia subject headings:
Castles--Italy--Milanese--Guidebooks.
Castles--Italy--Varese (Province)--Guidebooks.
Castles--Maggiore, Lake, Region (Italy and Switzerland)--Guidebooks.
Fortification--Italy--Milanese--Guidebooks.
Fortification--Italy--Varese (Province)--Guidebooks.
Fortification--Maggiore, Lake, Region (Italy and Switzerland)--Guidebooks.
Harvard subject headings:
Castles--Italy--Maggiore Lake, Region (Italy and Switzerland)--Guidebooks.
Castles--Italy--Milanese--Guidebooks.
Castles--Italy--Varese (Province)--Guidebooks.
Fortification--Italy--Maggiore Lake, Region (Italy and Switzerland)--Guidebooks.
Fortification--Italy--Milanese--Guidebooks.
Fortification--Italy--Varese (Province)--Guidebooks.
Princeton subject headings: