MLA

Harding, G. P. (George Perfect), 1780-1853, artist. L'Honorable Monsieur Thomas Walpole Membre du Parlemeni d'Angleterre & & & / [art original]. [ca. 1800]. https://collections.library.yale.edu/catalog/17469275.

APA, 6th edition

Harding, G. P. (George Perfect), 1780-1853, artist. ([ca. 1800])[L'Honorable Monsieur Thomas Walpole Membre du Parlemeni d'Angleterre & & & / [art original]]. https://collections.library.yale.edu/catalog/17469275.