Henry Pelham to John Singleton Copley, November 17, 1771, London Public Record Office (C05/39); Guernsey Jones, ed., The Letters and Papers of John Singleton Copley and Henry Pelham (Boston, 1914), pp. 114, 117, 174, 192, 197; Frank W. Bayley, The Life and Works of John Singleton Copley (Boston, 1915), p. 111; Barbara Neville Parker and Anne Bolling Wheeler, John Singleton Copley: American Portraits in Oil, Pastel, and Miniature with Biographical Sketches (Boston, 1938), p. 265; Charles Merrill Mount,“ A Hidden Treasure in Britain, Part II: John Singleton Copley,” Art Quarterly 24 (Spring 1961): 33-94; Jules David Prown, John Singleton Copley (Cambridge, Mass., 1966), pp. 60, 79, 80, 89, 214, 387, no. 284; Clifford Musgrave,“ Firle Place, Sussex,” Antiques 97 (February 1970): 260-66; John Russell, “A Portrait of Lady Returns,” New York Times, January 5, 1984; Valerie F. Brooks, “Tender Offer for Plain Jane,” Art News 83 (May 1984): 20; Julian Agnew, “Ideas from Heaven,” in Agnew’s, 1982-1992 (London, 1993), pp. 56-60; Carol Troyen, “John Singleton Copley and the Heroes of the American Revolution,” Antiques 148 (July 1995): 89, pl. VIII; Carrie Rebora and Paul Staiti, “John Singleton Copley in America,” American Art Review 7