Nardo di Cione, ‘Madonna and Child with Saint Peter and Saint John the Evangelist [left panel]’, probably c. 1360, National Gallery of Art, Washington, D.C.
left panel: 49.1 x 15.3 cm (19 5/16 x 6 in.)  overall (entire triptych): 76 x 66.4 cm (29 15/16 x 26 1/8 in.)