Columbia subject headings:
Piero, della Francesca, 1416?-1492--Criticism and interpretation--Congresses.
Harvard subject headings:
Piero, della Francesca, 1416?-1492--Criticism and interpretation--Congresses.
Science--Italy--History--Congresses.
Princeton subject headings:
Piero, della Francesca, 1416?-1492--Conferences.