> John Russell Fearn was a prolific science fiction and detective story writer who penned numerous books under a variety of pseudonyms. Each name signaled the genre in which he was working: Hugo Blayn, Spike Gordon and Dennis Clive for crime thrillers; Volstad Gridban, Vargo Statten, and Thornton Ayre for sci-fi pulp; John Slate for the detective novels featuring Maria Black; and many others. In some cases he blended sci-fi elements or, more accurately, scientific detection into his mystery novels. >>J. F. Norris, https://prettysinister.blogspot.com/2011/03/neglected-detectives-maria-black-ma.html