found: Astounding science fiction. Vol. LXIV, No. 1, 1959:title page (David Gordon)
found: Wikipedia, July 20, 2016(Randall Garrett; Randall Garrett (December 16, 1927-December 31, 1987) was an American science fiction and fantasy author; he was a prolific contributor to Astounding and other science fiction magazines of the 1950s and 1960s; Garrett wrote under a variety of pseudonyms including: David Gordon, John Gordon, Darrel T. Langart (an anagram of his name), Alexander Blade, Richard Greer, Ivar Jorgensen, Clyde Mitchell, Leonard G. Spencer, S. M. Tenneshaw, Gerald Vance)
found: The Encyclopedia of Science Fiction, via WWW, July 20, 2016(Garrett, Randall (1927-1987); US writer; his first publication was a Probability Zero vignette for Astounding Science-Fiction in 1944, and he went on to become a prolific writer for that magazine in the 1950s and early 1960s; he was at one time part of the Ziff-Davis stable writing for Amazing Stories and Fantastic, when he and his sometime collaborator Robert Silverberg ran a "fiction factory" together; during this prolific period Garrett used the pseudonyms David Gordon, Darrel T. Langart, Jonathan Blake MacKenzie and Seaton McKettrig as well as numerous House Names such as Alexander Blade, Richard Greer, Ivar Jorgensen, Clyde Mitchell, Leonard G. Spencer, S. M. Tenneshaw and Gerald Vance)