Portrait of Diego de Guevara (?). Dated: c. 1515/1518. Dimensions: overall: 33.6 x 23.7 cm (13 1/4 x 9 5/16 in.) framed: 54.9 x 46.3 cm (21 5/8 x 18 1/4 in.). Medium: oil on panel. Museum: National Gallery of Art, Washington DC. Author: Michel Sittow