Columbia subject headings:
Harvard subject headings:
Organ (Musical instrument)--Construction--Italy--Sicily--History.
Organ (Musical instrument)--Italy--Sicily--History.
Organ (Musical instrument)--Maintenance and repair.
Princeton subject headings:
Organ (Musical instrument)--Construction--Italy--Sicily--History.
Organ (Musical instrument)--Italy--Sicily--History.
Organ (Musical instrument)--Maintenance and repair.