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Piero della Francesca, Portraits of the Duke and Duchess of Urbino, Federico da Montefeltro and Battista Sforza, 1467-72, tempera on panel, 47 x 33 cm (Galleria degli Uffizi, Florence)

View this work up close on the Google Art Project:
http://www.googleartproject.com/collection/uffizi-gallery/artwork/portra...

http://www.googleartproject.com/collection/uffizi-gallery/artwork/portra...