SATAN'S WORLD - Lancer, 1st pb pr., 1968 - Very Good-           WE CLAIM THESE STARS - Ace, 1st solo pr.,1968 - VG+ to NF BEYOND THE BEYOND - Signet, 1st pr., 1969 - VG+                 by Poul Anderson                                                                       

Three Poul Anderson books, dealing almost entirely with interplanetary travel.  WORLD is part of the author's Polesotechnic League series (spine lean and some modest exterior wear).  STARS is the first "Flandry of Terra" novel (a bit of light edge/corner wear).  BEYOND consists of six novelets written in the 1950s & '60s (light spine crease & light corner wear).  Each of the books has a store stamp inside.