"The Foundations of Marxist-Leninist Ethics", Studies in Soviet Thought, III (1963), pp. 121-133, 1963, Box: 13, Folder: 7. 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/315340 Accessed June 20, 2025.