Asimov, Isaac. and Greenberg, Martin. H, eds, THE GREAT SF STORIES #16, (1954, , 1987

Asimov, Isaac. and Greenberg, Martin. H, eds, THE GREAT SF STORIES #16, (1954, , 1987, Box: 31, Folder: 29. Donald A. Wollheim papers, MS 250. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/242269 Accessed December 25, 2025.