MLA

Johnson, James Weldon, 1871-1938. Pickens, William. Box 16, folder 377. 1934-37. https://collections.library.yale.edu/catalog/16748001.

APA, 6th edition

Johnson, James Weldon, 1871-1938. (["Box 16, folder 377"])(1934-37)[Pickens, William]. https://collections.library.yale.edu/catalog/16748001.