Archivo:Niccolò Tartaglia.jpg

, from http://web4.si.edu/sil/scientific-identity/display_results.cfm?alpha_sort=W

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Access to and use of digital image files, text, and data used on this web site are subject to the following terms and conditions. By using these materials, the user is deemed to have consented to the terms and conditions set forth below. For Smithsonian policy on this topic see: http://www.si.edu/copyright/

The digital image files and associated text on this web site are the property of the Smithsonian Institution or of other institutions or individuals.

The Smithsonian images are made available for non-commercial educational or personal use only.

And according to http://www.si.edu/copyright/ :

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Why PD?