Birkhoff, George D. The Origin, Nature, and Influence of Relativity, New York, NY : The MacMillan Company, 1925

Birkhoff, George D. The Origin, Nature, and Influence of Relativity, New York, NY : The MacMillan Company, 1925. Personal papers of G. Baley Price, PP 523. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/127595 Accessed April 14, 2026.