MLA

Whitman, Walt, 1819-1892. Holograph notes, corrected. Box 3, folder 146. 1888. https://collections.library.yale.edu/catalog/2007255.

APA, 6th edition

Whitman, Walt, 1819-1892. (["Box 3, folder 146"])(1888)[Holograph notes, corrected]. https://collections.library.yale.edu/catalog/2007255.