MLA

Hunter, Mary Smyth, 1856-1933. Moore, George. Box 2, folder 51-54. 1896-1932, undated. https://collections.library.yale.edu/catalog/16834498.

APA, 6th edition

Hunter, Mary Smyth, 1856-1933. (["Box 2, folder 51-54"])(1896-1932, undated)[Moore, George]. https://collections.library.yale.edu/catalog/16834498.