See also: Vulcan's Hammer  

(1956): FUTURE #29 {Cover and ill. by Freas}
(1959 Aug): SATELLITE #20 {tr. into French as LES MARTEAUX DE VULCAIN}

(1960): VULCAN'S HAMMER, Ace, pb, D457, $0.35 {expanded into novel}

(1963): SIX AND THE SILENT SCREAM {Ed.: Howard} Belmont, pb