Collection (vol. 1 - 1952, vol. 55 - 1994) is one of the most authoritative publications in mathematics and includes original monographic articles on topical problems of modern mathematics. Volume 56 covers a wide range of topics. It publishes studies on partial differential equations, mathematical physics, asymptotic theory of ordinary equations and stochastic analysis. There are articles devoted to triangular groups and three-dimensional orbifolds, as well as moduli theory.