Fresco by the Italian Renaissance master Piero della Francesca, painted around 1463-65 CE.
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Original image by Piero della Francesca. Uploaded by Cristian Violatti, published on 31 March 2014 under the following license: Creative Commons: Attribution-NonCommercial-ShareAlike. This license lets others remix, tweak, and build upon this content non-commercially, as long as they credit the author and license their new creations under the identical terms.