lower left in plate: James Smithson Marshal of the King's Bench / 1422~ / Sketch'd by J. H. Mortimer; lower right in plate: Alice Whitworth Wife of James, died without / Issue 1436.~ / Etch'd by R. Blyth; lower center in plate: Publish'd as the Act directs Feb.y 20th 1780 by R. Blyth; by later hand, lower left in graphite: T; by later hand, lower right in graphite: Box 32
(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 (1988): no. 281