MLA

Gibbons, Sandra, 1982-, artist. NOTHING ELEGANT [and] MILDRED'S UMBRELLA. Box 1 | Folder 10. 2011. https://collections.library.yale.edu/catalog/16068724.

APA, 6th edition

Gibbons, Sandra, 1982-, artist. (["Box 1 | Folder 10"])(2011)[NOTHING ELEGANT [and] MILDRED'S UMBRELLA]. https://collections.library.yale.edu/catalog/16068724.