MLA

Johnson, James Weldon, 1871-1938. Johnsons, Walter White, and John E. Nail, Great Barrington, Massachusetts. Box 109, folder 958. circa 1926. https://collections.library.yale.edu/catalog/15814937.

APA, 6th edition

Johnson, James Weldon, 1871-1938. (["Box 109, folder 958"])(circa 1926)[Johnsons, Walter White, and John E. Nail, Great Barrington, Massachusetts]. https://collections.library.yale.edu/catalog/15814937.