Cite

Lionni, Leo, 1910-1999

MLA

Steinberg, Saul, 1914-1999. Lionni, Leo, 1910-1999. Box 27, folder 499. 1958 November 15, undated. https://collections.library.yale.edu/catalog/2044055.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 27, folder 499"])(1958 November 15, undated)[Lionni, Leo, 1910-1999]. https://collections.library.yale.edu/catalog/2044055.