G. Glück, Van Dyck: des Meisters Gemälde (Klassiker der Kunst) , Stuttgart and Berlin 1931, p. 533, under nos 126 and 127;
L. van Puyvelde, in Le Siècle de Rubens , exh. cat., Brussels 1965, pp. 62-63, under no. 61;
M. Jaffé, 'Van Dyck's sketches for his portraits of Duquesnoy and Van Uffel', in Bulletin des Musées Royaux des Beaux-Arts de Belgique , 1967, pp. 160-61, reproduced;
O. Millar, 'Van Dyck at Agnews', in The Burlington Magazine , vol. 110, 1968, p. 712 ('has the brilliance of the best of the Iconography sketches');
J.S. Held, The collections of the Detroit Institute of Arts, Flemish and German paintings of the 17th century , Detroit 1982, p. 30;
W.A. Liedke, Flemish Painting in the Metropolitan Museum of Art , New York 1984, p. 59 (as attributed to Van Dyck);
S.J. Barnes, Van Dyck in Italy , doctoral diss., New York University, 1986, pp. 257-8, no. 42;
E. Larsen, The Paintings of Van Dyck , Freren 1988, vol. II, p. 171, no. 149, reproduced;
J.S. Held, in Anthony van Dyck, exh. cat., Washington 1990, pp. 339-41, no. 92, reproduced;
H. Vey, in S.J. Barnes, N. de Porter. O. Millar and H. Vey , Van Dyck, A Complete Catalogue of the Paintings, New Haven and London 2004, pp. 208-09, no. II.69, reproduced in colour.