MLA

Douglas, Norman, 1868-1952. "T" General. Box 46. 1937-1949, undated. https://collections.library.yale.edu/catalog/16454765.

APA, 6th edition

Douglas, Norman, 1868-1952. (["Box 46"])(1937-1949, undated)["T" General]. https://collections.library.yale.edu/catalog/16454765.