Francis Blackburne, Memoirs of Thomas Hollis, vol 2, London: J. Nicholls, 1780, p. 502
John Chaloner Smith, British mezzotinto portraits, vol. 2, London 1878, p. 885 ("138. Sir Isaac Newton. Seeman. Short H. L., directed towards right, facing towards and looking to front, long white hair, plain coat, cravat with long fall. Under, on grounded space, Sir Isaac Newton drawn and scraped MDCCLX by lames Macardel from an original portrait painted by Enoch Seeman now in the possession of Thomas Hollis F.R. and A. SS. Les Italiens ces peuples ingénieux — encore. Ode sur la mort de Madame de Bareith avec une lettre par Mons. de Voltaire. At bottom a cap. … I. As described. II. Retouched, ground lighter, button seen on coat. See page 401. The cap is a symbol of the republican ideas of Mr. Holles.")
R. Burgess, Portraits of doctors & scientists in the Wellcome Institute, London 1973, no. 2140.35
M. Keynes, The iconography of Sir Isaac Newton to 1800, Woodbridge, Suffolk, 2005, no. XLIX-1, p. 59