Columbia subject headings:
Altars in art.
Altars--Italy--Ravenna.
Mosaics--Italy--Ravenna.
Harvard subject headings:
Altars in art.
Altars--Italy--Ravenna.
Christian art and symbolism--Italy--Ravenna.
Church decoration and ornament--Italy--Ravenna--Themes, motives.
Mosaics--Italy--Ravenna
Princeton subject headings:
Altars in art.
Altars--Italy--Ravenna.
Mosaics--Italy--Ravenna.