Gregory Kern is a pseudonym of E. C. Tubb.
Edwin Charles Tubb was a British writer of science fiction, fantasy and western novels. The author of over 140 novels and 230 short stories and novellas, using 58 pen names over five decades of writing, although some of these were publishers' house names also used by other writers. Tubb wrote 17 Cap Kennedy novels, all under the pseudonym Gregory Kern. - Wikipedia
