Signature: In plate, lower right: "TFrye 1761"
Chaloner Smith 21; Russell 21
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. II, p. 521, no. 21.
Charles E. Russell English Mezzotinto Portraits and Their States. vol. II, London and New York, 1926, vol. II, p. 113, no. 21 (identifies sitter).