Lem, Stanislaw. "The Time-Travel Story and Related Matters of SF Structuring"
Comments: Discusses SF treatments of time-travel, paradox loops, and the chronocracy (including Ray Bradbury's "A Sound of Thunder", Ward Moore's Bring the Jubilee, and Isac Asimov's The End of Eternity) in terms of the philosophical or historical inquiry present in the text.
Published: In Science-Fiction Studies vol. 1, no. 3, pp. 143-154 (Spring 1974).