Catalogue of Important Modern Pictures . . . the Property of John H. Foster, Esq. Deceased; late of Fernside, Witley, Surrey. Christie's, London. March 24, 1906, p. 8, no. 31, calls it Nell Gwyn and notes that Peter Cunningham mentions it in "Story of Nell Gwyn," p. 173.
Bryson Burroughs. The Metropolitan Museum of Art: Catalogue of Paintings. 9th ed. New York, 1931, p. 209, no. L534–3, calls it "Nell Gwynne" and describes it as unfinished.
R. B. Beckett. Letter. April 21, 1948 [letter unlocated; transcript only], accepts the attribution to Lely.
R. B. Beckett. Letter. December 24, 1948 [letter unlocated; transcript only], accepts the attribution, dates the picture in the 1670s, but rejects the identification of the sitter as Nell Gwynn.
Five Centuries of European Painting. Exh. cat., Arkansas Arts Center. Little Rock, 1963, p. 25, ill., suggests that the sitter is probably the duchess of Cleveland.
Oliver Millar. Letter to Mary Sprinson. July 31, 1978, refers to it from memory as "Unfinished head of [a] girl. Late, probably right".
Katharine Baetjer. British Paintings in The Metropolitan Museum of Art, 1575–1875. New York, 2009, pp. 22–23, no. 9, ill. (color).