MLA

James, Rebecca Salsbury, 1891-1968. McCausland, Elizabeth. Box 1a, folder 26-27. 1951-63. https://collections.library.yale.edu/catalog/32471796.

APA, 6th edition

James, Rebecca Salsbury, 1891-1968. (["Box 1a, folder 26-27"])(1951-63)[McCausland, Elizabeth]. https://collections.library.yale.edu/catalog/32471796.