Typescript (in looseleaf binder labeled "Vortice trains produced by trough cup blocking of slit nozzle jets, 1971 and 1972"), with sketches and ink spray test results, Box: 9, Folder: 5. Russell Randolph Hays papers, RH MS 564. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/278238 Accessed November 23, 2024.