Cite

Enough to make an angel swear, or, Real birds plucking the sham [graphic]

MLA

Seymour, Robert, 1798-1836, printmaker. Enough to make an angel swear, or, Real birds plucking the sham [graphic]. [approximately 1828]. https://collections.library.yale.edu/catalog/15956799.

APA, 6th edition

Seymour, Robert, 1798-1836, printmaker. ([approximately 1828])[Enough to make an angel swear, or, Real birds plucking the sham [graphic]]. https://collections.library.yale.edu/catalog/15956799.