Self-Portrait Aged 24, 1639, oil on panel, 65.8 x 54.4 cm, signed and dated, bottom right, "G. Flinck 1639," National Gallery of Art, London, inv. NG4068.. See Werner Sumowski, Drawings of the Rembrandt School, 10 vols.(New York, 1979–92), 4: 1896–97, no. 867. This observation has already been made in Horst Gerson, Rembrandt's Influence in the Seventeenth Century: Catalogue of a Loan ...