Columbia subject headings:
Harvard subject headings:
Art, Italian--Italy--Siena.
Art, Renaissance--Italy--Siena.
Organ (Musical instrument) in art.
Organ (Musical instrument)--Italy--Siena--History.
Princeton subject headings:
Art, Italian--Italy--Siena.
Art, Renaissance--Italy--Siena.
Organ (Musical instrument) in art.
Organ (Musical instrument)--Italy--Siena--History.