MLA

Mayer, Elizabeth (1884-1970). Pearson, Norman Holmes. Box 1, folder 2-4. 1936-1966. https://collections.library.yale.edu/catalog/10259924.

APA, 6th edition

Mayer, Elizabeth (1884-1970). (["Box 1, folder 2-4"])(1936-1966)[Pearson, Norman Holmes]. https://collections.library.yale.edu/catalog/10259924.