MLA

Steinberg, Saul, 1914-1999. Untitled [Abraham Lincoln kicking a child in the rear, headed towards a "Gingerbread" house with fountain in the yard]. Box 414, folder 5538. undated. https://collections.library.yale.edu/catalog/16849919.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 414, folder 5538"])(undated)[Untitled [Abraham Lincoln kicking a child in the rear, headed towards a "Gingerbread" house with fountain in the yard]]. https://collections.library.yale.edu/catalog/16849919.