MLA

Ford, Julia Ellsworth, 1859-1950. Gregory, Lady. Box 1, folder 32. 1911 November 19. https://collections.library.yale.edu/catalog/17167829.

APA, 6th edition

Ford, Julia Ellsworth, 1859-1950. (["Box 1, folder 32"])(1911 November 19)[Gregory, Lady]. https://collections.library.yale.edu/catalog/17167829.