A.J. Finberg, A Complete Inventory of the Drawings of the Turner Bequest, London 1909, vol.I, p.596, CXCV 177a, as ‘177. Glass balls, partly filled with water’.
Judy Egerton [and Clifford Ellis], ‘JMWT PP’: A Selection of Drawings Made by Turner to Illustrate his Royal Academy Lectures as Professor of Perspective, exhibition catalogue, Tate Gallery, London 1980, p., as ‘Glass sphere’.
Thomas H. Coolsen, ‘Phryne and the Orators: Decadence and Art in Ancient Greece and Modern Britain’, Turner Studies, vol.7 no1, Summer 1987, pp.7, 10 note 33.
Maurice Davies, Turner as Professor: The Artist and Linear Perspective, exhibition catalogue, Tate Gallery London 1992, p.53, reproduced fig.52.
Maurice William Davies, ‘J.M.W. Turner’s Approach to Perspective in His Royal Academy Lectures of 1811’, unpublished Ph.D thesis, Courtauld Institute of Art, London 1994, p.265.