Cite

Evans's Map 1 (the Expedition's route about August 13-September 10, 1804)

MLA

Lewis, Meriwether, 1774-1809. Evans's Map 1 (the Expedition's route about August 13-September 10, 1804). Box 1 | Folder 4. undated. https://collections.library.yale.edu/catalog/2002445.

APA, 6th edition

Lewis, Meriwether, 1774-1809. (["Box 1 | Folder 4"])(undated)[Evans's Map 1 (the Expedition's route about August 13-September 10, 1804)]. https://collections.library.yale.edu/catalog/2002445.