MLA

Adams, Léonie, 1899-1988. Villa, Jose Garcia. Box 3, folder 270. 1954 April 26. https://collections.library.yale.edu/catalog/17204538.

APA, 6th edition

Adams, Léonie, 1899-1988. (["Box 3, folder 270"])(1954 April 26)[Villa, Jose Garcia]. https://collections.library.yale.edu/catalog/17204538.