"The Uneasy Revival of Metaphysics", The Review of Metaphysics, X (1963), pp. 68-81, 1963, Box: 13, Folder: 4. Personal papers of Richard T. De George, PP 531. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/315337 Accessed June 22, 2025.