Columbia subject headings:
Piazza del popolo (Ravenna, Italy)
Plazas--Italy--Ravenna.
Ravenna (Italy)--Buildings, structures, etc.
Harvard subject headings:
Piazza del popolo (Ravenna, Italy)
Plazas--Conservation and restoration--Italy--Ravenna.
Princeton subject headings:
Piazza del popolo (Ravenna, Italy)
Plazas--Conservation and restoration--Italy--Ravenna.