This Sci-Fi 6-Pack contains six novels from the pulp era and the Golden Age of Science Fiction, spanning the 1930s to the 1960s. A few earlier works are also included. Many of the masters of science fiction are here, including works by Harry Harrison, Raymond F. Jones, Murray Leinster, Alan Nourse, H. Beam Piper, and Mack Reynolds. Includes an active table of contents for easy navigation.SENSE OF OBLIGATION, Harry HarrisonTHE GREAT GRAY PLAGUE, Raymond F. JonesFIFTH-DIMENSION TUBE, Murray LeinsterGOLD IN THE SKY, Alan E. NourseFOUR-DAY PLANET, H. Beam PiperBORDER, BREED NOR BIRTH, Mack Reynolds