Columbia subject headings:
Bologna (Italy)--Buildings, structures, etc.--Pictorial works.
Historic buildings--Italy--Bologna--Pictorial works.
Palaces--Italy--Bologna--Pictorial works.
Staircases--Italy--Bologna--Pictorial works.
Stairs--Italy--Bologna--Pictorial works.
Harvard subject headings:
Architecture--Italy--Details--History--17th century--Pictorial works.
Architecture--Italy--Details--History--18th century--Pictorial works.
Architecture--Italy--Details--History--19th century--Pictorial works.
Historic buildings--Italy--Bologna--Pictorial works.
Palaces--Italy--Bologna--Pictorial works.
Staircases--Italy--Bologna--Pictorial works.
Princeton subject headings:
Bologna (Italy)--Buildings, structures, etc.--Pictorial works.
Historic buildings--Italy--Bologna--Pictorial works.
Palaces--Italy--Bologna--Pictorial works.
Staircases--Italy--Bologna--Pictorial works.
Stairs--Italy--Bologna--Pictorial works.