13 Above the Night, a reprint-anthology edited by Groff Conklin (1965.) Stories are from 1951 to 1963: 5 from Galaxy, 4 from Magazine of F&SF, 2 from Astounding/Analog, plus 1 each from Venture and Startling Stories.

Contents:
Introduction by Groff Conklin
"Founding Father" by J. F. Bone
"Mating Call" by Frank Herbert
"Nice Girl With Five Husbands" by Fritz Leiber
"Prone" by Mack Reynolds
"The Education of Tigress McCardle" by C. M. Kornbluth
"Now Inhale" by Eric Frank Russell
"The Back of Our Heads" by Stephen Barr
"Button, Button" by Isaac Asimov
"The Deep Down Dragon" by Judith Merril
"The Kappa Nu Nexus" by Avram Davidson
"Idiot Solvant" by Gordon R. Dickson
"Counter Security" by James White
"The Dreistein Case" by J. Lincoln Paine.

Conklin was a freelance editor, producing almost 40 anthologies large and small from 1946 until his death in 1968. He was book reviewer for Galaxy for the first 5 years (through October 1955.) Most will agree that he had good taste, and his anthologies were considered and capable. If you want some good reading - of the sort that you may not find easily, look here. Unless you have a really, really large magazine collection, you are likely to find a combination of stories and authors that you don't have or are curious about.