Reprints from the Journal of Biological Chemistry, January 1921, May 1921, 1921-01, 1921-05, Box: 3, Folder: 76. Personal Papers of Elmer V. McCollum, PP 120. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/188956 Accessed January 15, 2025.