The model of this sculpture must be attributed to the ambit of Guglielmo della Porta. It is identical to that of the Walters House Museum, where it is cataloged "after Guglielmo della Porta's model ". Furthermore, it appears to be very similar to the model belonging to the "Quentin Collection" (published in the catalog of the exhibition held at the Frick Collection in 2004-2005 in New York), from which it differs mainly in the orientation of the gaze (the Quentin model Collection looks to its left).