Snail on the Slope (Russian - "Улитка на склоне") is a science fiction novel by Soviet authors Boris and Arkady Strugatsky. The first version of the novel was written in 1965 (during March 6 and 20), but then it was significantly rewritten. The original draft was published in 1990 under the title Disquiet. In the spring of 1966 the so-called "Forest" part of the novel was separately published in the USSR. In 1968 the other part was published, in the journal "Baikal". A full version was published in 1972 in the Federal Republic of Germany and in the USSR in 1988. The brothers Strugatsky have described this novel as the most perfect and the most valuable of their works. Source: Wikipedia (en)