Sonderdruck aus: Bielefelder Symposium uber Attribution [Authors-Herausgegeben von Dietmar Gorlitz, Wulf-Uwe Meyer, and Bernard Weiner, Box: 39, Folder: 50. Personal papers of Fritz Heider, PP 343. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/122586 Accessed June 26, 2024.