Columbia subject headings:
Harvard subject headings:
Architecture, Medieval--Italy--Palermo.
City planning--Italy--Palermo--History--To 1500.
Palermo (Italy)--Buildings, structures, etc.
Princeton subject headings:
Architecture, Medieval--Italy--Palermo.
City planning--Italy--Palermo--History--To 1500.
Palermo (Italy)--Buildings, structures, etc.