John Chaloner Smith British Mezzotinto Portraits...from the introduction of the art to the early part of the present century. Henry Sotheran & Company, vols. 1-4, 1878–83, vol. I, p. 173, no. 4.
Edward Hamilton The Engraved Works, 1755-1822, of Sir Joshua Reynolds. London, 1884 (reprinted 1973), p. 4 iii/iii.
Freeman O'Donoghue Catalogue of Engraved British Portraits Preserved in the Department of Prints and Drawings in the British Museum. vols. 1-5, London, 1908–22, vol. I, p. 113, no. 14.