Cite

Mrs. Siddons after Gainsborough [art original]

MLA

Cosway, Richard, 1740-1821, artist. Mrs. Siddons after Gainsborough [art original]. [ca. 1900]. https://collections.library.yale.edu/catalog/15815150.

APA, 6th edition

Cosway, Richard, 1740-1821, artist. ([ca. 1900])[Mrs. Siddons after Gainsborough [art original]]. https://collections.library.yale.edu/catalog/15815150.