[ZWoz]

Arkady and Boris Strugatsky. If you start with their earliest work, like "The Land of Crimson Clouds", you can get vibe, how communist Sci-Fi looked. If you read later stuff, like "Tale of the Troika", then you get story humorously criticizing soviet bureaucracy. Then there is pretty serious stuff, like "The Doomed City" or "Ugly Swans". You probably know "Roadside Picnic" - this interpretations in films and gaming are known as "Stalker".