MLA

Hilles, Frederick W. (Frederick Whiley), 1900-1975. Reynolds family. Box 32 (Oversize), folder 891. undated. https://collections.library.yale.edu/catalog/2041834.

APA, 6th edition

Hilles, Frederick W. (Frederick Whiley), 1900-1975. (["Box 32 (Oversize), folder 891"])(undated)[Reynolds family]. https://collections.library.yale.edu/catalog/2041834.