MLA

Hill, A. J. (Alfred James), 1823-1895. Letter : St. Paul, Minnesota Territory, to John Hotten, London England, 1857 Aug 22.. 1857 August 22. https://collections.library.yale.edu/catalog/11703559.

APA, 6th edition

Hill, A. J. (Alfred James), 1823-1895. (1857 August 22)[Letter : St. Paul, Minnesota Territory, to John Hotten, London England, 1857 Aug 22.]. https://collections.library.yale.edu/catalog/11703559.