Paul Myron Anthony Linebarger to Hary Altshuler on "On the Sand Planet", March 11, 1965, Box: 6a, Folder: D1.La.5. Cordwainer Smith papers, MS 196. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/550334 Accessed January 17, 2025.