MLA

Carson, Rachel, 1907-1964. Dutch Elm disease. Box 32, folder 572-74. 1960-63, n.d.. https://collections.library.yale.edu/catalog/16845843.

APA, 6th edition

Carson, Rachel, 1907-1964. (["Box 32, folder 572-74"])(1960-63, n.d.)[Dutch Elm disease]. https://collections.library.yale.edu/catalog/16845843.