lower left in plate: Drawn by J. H. Mortimer; lower center in plate: Conversing with a Captive. / London, Publish'd as the Act directs 15th Nov. 1779 by R. Blyth, No. 27 Great Castle Street, Cavendish Square; lower right in plate: Etched by R. Blyth
(Campbell Fine Art, London, 4 May 1992); Donald Vogler, Portland, OR; gift to NGA, 2017.
- Sunderland, John. "John Hamilton Mortimer: His Life and Works," Walpole Society 52 (1986): no. 71.2