Priscilla Muller suggested, on the basis of a photograph, that the present drawing is comparable, although not by the same hand, with a group of early 17th Century Sevillian studies influenced by Pacheco, D. Angulo and A.E. Pérez Sánchez, A Corpus of Spanish Drawings, Seville 1600-1650, Oxford, 1985, nos. 107-8 and 111-2, pls. XXXVIII-IX