Tight and almost square ; spine is flat with a line down middle and light wear. Both front covers look rather nice / wear limited to spine. No stamps, marks or writing.

An Ace Double containing The Door Through Space by Marion Zimmer Bradley, bound with Rendezvous on a Lost World by A. Bertram Chandler. The first edition was 1961 (F-117 / short format); it was reprinted in 1972 (tall format) - both times as an Ace Double.

The Door Through Space by Marion Zimmer Bradley (115 pages; cover by Enrich.) At one time Race Cargill had been the best Terran Intelligence agent on the complex and mysterious planet of Wolf. He had repeatedly imperiled his life amongst the half-human and non-human creatures of the sullen world. And he had repeatedly accomplished the fantastic missions until his name was emblazoned with glory. But that had all suddenly ended. For 6 long years he'd sat behind a boring desk inside the fenced-in Terran Headquarters, cut off there ever since he and a rival had scarred and ripped each other in blood-feud. But when the DOOR THROUGH SPACE swung suddenly open, the feud was on again - and with it a plot designed to check and destroy the Terran Empire. This is sort-of a "Darkover" book, for much of the action takes place in the Dry-Towns, a locale which Bradley later shifted to be part of Darkover (Cottman IV.)

(Bound with) Rendezvous on a Lost World by A. Bertram Chandler (cover by John Schoenherr, 105 pages.) Shorter (?) version in Amazing February 1961 as "When the Dream Dies."
Alan Kemp dreams of being owner and master of a spaceship, quietly running the Eastern Circuit within reach of his home and wife - "his dream belonged to the black emptiness between the stars." Obsessed by this ambition, Kemp leads his 3 comrades and their second-hand spaceship Lucky Lady into the dangerous Lost Colonies, which are inhabited by hostile and vicious criminals on the run from justice. They are attacked by Baron Bligh and his armed horsemen, and are also taken prisoner by a Robot Controlled Intelligence. Here they encounter beautiful robot women, self-igniting cigarettes, mechanic octopoids and glittering metallic crabs. Just how much will a man sacrifice to realize a dream?