The Second IF Reader of Science Fiction
by Frederik Pohl, Brian W. Aldiss, Isaac Asimov, J. G. Ballard, Algis Budrys, Hal Clement, David A. Kyle, Keith Laumer, Larry Niven, Fred Saberhagen
In the Arena, 1963, Brian W. Aldiss
The Billiard Ball, 1967, Isaac Asimov
The Time-Tombs, 1963, J. G. Ballard
"Die, Shadow!", 1963, Algis Budrys
The Foundling Stars, 1966, Hal Clement
Toys for Debbie, 1965, David A. Kyle
Forest in the Sky, [Retief], 1967, Keith Laumer
At the Core, [Known Space], 1966, Larry Niven
Under Two Moons, 1965, Frederik Pohl
Masque of the Red Shift, [Berserker], 1965, Fred Saberhagen