Columbia subject headings:
Harvard subject headings:
Architecture--Italy--Tivoli--Guidebooks.
Tivoli (Italy)--Antiquities, Roman--Guidebooks.
Tivoli (Italy)--Buildings, structures, etc.--Guidebooks.
Tivoli (Italy)--Guidebooks.
Princeton subject headings:
Guidebooks.
Tivoli (Italy)--Guidebooks.