Use of Alger Explorer "X" - The super-sensitive subterranean isotope sensor

Use of Alger Explorer "X" - The super-sensitive subterranean isotope sensor, Box: 4, Folder: 64. Wallace E. Pratt papers, RH MS 870. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/34072 Accessed December 25, 2025.