Columbia subject headings:
City planning--Italy--Siena.
Siena (Italy)--Buildings, structures, etc.
Siena (Italy)--Description and travel.
Siena (Italy)--Pictorial works.
Harvard subject headings:
Aerial photography--Italy--Siena.
Siena (Italy)--Aerial photographs.
Siena (Italy)--Buildings, structures, etc.--Pictorial works.
Princeton subject headings:
Aerial photography--Italy--Siena.
Siena (Italy)--Aerial photographs.
Siena (Italy)--Buildings, structures, etc.--Pictorial works.