Great collection of action short stories by Frederik Pohl from "The Golden Age of Science Fiction". Featured here: "The Tunnel Under the World", "The Day of the Boomer Dukes", "The Hated", "Pythias", "The Knights of Arthur", "My Lady Greensleeves", and "Survival Kit".
Frederik George Pohl Jr. (November 26, 1919 – September 2, 2013) was an American science-fiction writer, editor, and fan, with a career spanning more than 75 years—from his first published work, the 1937 poem "Elegy to a Dead Satellite: Luna", to the 2011 novel All the Lives He Led and articles and essays published in 2012.