Cite

[Portrait of Sir Edward Walpole] [art original].

MLA

Edwards, Edward, 1738-1806, artist. [Portrait of Sir Edward Walpole] [art original].. [not after 1784]. https://collections.library.yale.edu/catalog/16731047.

APA, 6th edition

Edwards, Edward, 1738-1806, artist. ([not after 1784])[[Portrait of Sir Edward Walpole] [art original].]. https://collections.library.yale.edu/catalog/16731047.