MLA

Cruikshank, Robert, 1789-1856, artist. Chelsea pensioners [art original].. [before 1856]. https://collections.library.yale.edu/catalog/17339769.

APA, 6th edition

Cruikshank, Robert, 1789-1856, artist. ([before 1856])[Chelsea pensioners [art original].]. https://collections.library.yale.edu/catalog/17339769.