Columbia subject headings:
Architecture, Domestic--Italy--Siena.
Architecture--Italy--Siena--History--17th century.
Architecture--Italy--Siena--History--18th century.
Siena (Italy)--Buildings, structures, etc.
Harvard subject headings:
Architecture, Domestic--Italy--Siena.
Architecture--Italy--Siena--History.
Architecture--Italy--Siena.
Palaces--Italy--Siena.
Siena (Italy)--Buildings, structures, etc.
Princeton subject headings: