Columbia subject headings:
Art, Italian--Italy--Po River Valley.
Art, Romanesque--Italy--Po River Valley.
Church decoration and ornament--Italy--Po River Valley.
Harvard subject headings:
Art, Italian--Italy--Po River Plain.
Art, Romanesque--Italy--Po River Plain.
Church decoration and ornament--Italy--Po River Plain.
Princeton subject headings:
Art, Italian--Italy--Po River Valley.
Art, Romanesque--Italy--Po River Valley.
Church decoration and ornament--Italy--Po River Valley.