Cite

[Isabella comforting the dying knight] [art original].

MLA

[Isabella Comforting the Dying Knight] [Art Original]. 0AD. https://collections.library.yale.edu/catalog/16704399.

APA, 6th edition

[Isabella comforting the dying knight] [art original]. (0 C.E.). [Illustrations, Watercolors British 19th century]. https://collections.library.yale.edu/catalog/16704399.