Galactic Patrol - Lensman Series Book 3
E.E. 'Doc' Smith's classic Lensman series
The space pirates of Boskone raided at will, menacing the whole structure of interstellar civilization. Master minded by a super scientist, their conquering fleets outgunned even the mighty space cruisrs of the Galactic Patrol.
When Lensman Kim Kinnison of the Patrol discoverd the secret Boskonian base, it was invulnerable to outside attack. But where a battle fleet would meet insuperable resistance, a single infiltrator might penetrate the Boskonian defences
Quality rated as good = signs of wear, creases on spine and cover, some writing on first page