Columbia subject headings:
Church doorways--Italy--Siena.
Duomo di Siena.
Giovanni, d'Agostino, 1310-approximately 1348.
Marble sculpture--Conservation and restoration--Italy--Siena.
Harvard subject headings:
Church doorways--Italy--Siena.
Duomo di Siena.
Giovanni, d'Agostino, 1310-approximately 1348
Marble sculpture--Italy--Siena--Conservation and restoration.
Princeton subject headings:
Church doorways--Italy--Siena.
Duomo di Siena.
Giovanni, d'Agostino, 1310-approximately 1348.
Marble sculpture--Conservation and restoration--Italy--Siena.