Letter from <a href="https://en.wikipedia.org/wiki/Cosimo_I_de%27_Medici,_Grand_Duke_of_Tuscany" class="extiw" title="w:Cosimo I de' Medici, Grand Duke of Tuscany">Cosimo I de’ Medici, Grand Duke of Tuscany</a>, to the Humanist Piero Vettori (1499–1585). According to the date at the end, written “xx di Aprile 1549”. While the letter was obviously written by some professional writer (as usual in that time), the signature at the end seems authentic.
Cosimo I de' Medici
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