1954 was a good year for Poul Anderson. This was the year he published his first major science fiction novel (the classic Brain Wave), the classic fantasy The Broken Sword, and the also-classic rationalized fantasy adventure Three Hearts and Three Lions. Not yet thirty, he had already begun some of his most famous series: stories about the Hoka, Dominic Flandry, and his Future History/Technic Civilization. And 1954 also saw the magazine publication of a quirky story called Question and Answer in the June and July issues of Astounding Science Fiction.
Question and Answer was both an alien encounter story and a puzzle story. In this case, the puzzle concerns the aliens: a contradictory conumdrum that faces some interplanetary explorers. To go much further would give much of the plot away. Convincing and logical depictions of aliens that are alien are relatively rare in science fiction: Stanley G. Weimbaum pointed the way in A Martian Odyssey, Hal Clement convinced us with his Mesklinites in Mission of Gravity, and Poul Anderson turned a new leaf with this story. (Yes, I know there are many other examples in science fiction today, especially since many sf writers now have a solid grounding in science, but right now I'm in my gosh-wow, wide-eyed, golden-age mind set. So quitcha carping and go read the story.)
Question and Answer was published in paperback by Ace in 1956 under the title Planet of No Return, and has been repirinted a number of times, including a 1978 reprint under the original magazine title Question and Answer. The novel has also been been included in two omnibuses of Anderson's work: The Worlds of Poul Anderson (Ace, 1974; do not confuse with the Roger Elwood-edited collection of Anderson's work titled The Many Worlds of Poul Anderson) and Two Worlds (Gregg Press, 1978).
Anderson, of course, continued on writing -- creating more and more marvelous world and garnering more and more fans and awards until his death in 2001 at age 74. For those who have not read his books, you can start almost anywhere (I have not read anything by Poul Anderson that I have not enjoyed) -- he has written science fiction, fantasy, mystery, historicals, adventure, juveniles, poetry, and non-fiction -- but if you're looking for a good, entertaining, fast-paced, sense-of-wonder read, try Planet of No Return.