Business card: A. L. Duncan (Fairbanks, Morwe Co.), n.d.; illustration of Hays invention [untitled], n.d, Box: 6, Folder: 3. Russell Randolph Hays papers, RH MS 564. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/278171 Accessed November 27, 2024.