MLA

MacDonald, George, 1824-1905. Bicknell, Clarence. Box 1, folder 43. 1879. https://collections.library.yale.edu/catalog/16474487.

APA, 6th edition

MacDonald, George, 1824-1905. (["Box 1, folder 43"])(1879)[Bicknell, Clarence]. https://collections.library.yale.edu/catalog/16474487.