of Vyacheslav Stepanov. Supervising his activities, Stepanov identified himself as the scientific advisor of his younger colleague. After his graduation, in 1935, Demidovich worked for one semester at the Department of Mathematics at the Institute for the leather industry. And, since February 1936, at the invitation of LA Tumarkin, he served as assistant chair of mathematical analysis of Mechanics and Mathematics Faculty of Moscow State University. Until his death he remained a permanent staff member. In 1935 at the Moscow University, Demidovich discussed his PhD thesis, "On the existence of the integral invariant on a system of periodic orbits" and the following year, he was awarded the degree of Ph.D. In 1938, Demidovich was granted the rank of assistant professor of mathematical analysis at Mehmat MSU. In 1963, VAK awarded him the degree of Doctor of physical and mathematical sciences, and in 1965, Demidovich was granted the rank of professor in the department of mathematical analysis at Mehmat MSU. In 1968, the Presidium of the Supreme Council of Russia awarded Demidovich the honorary title "Meritorious Scientist of the RSFSR". Demidovich suddenly died on 23 April 1977 of acute cardiovascular insufficiency. Scientific activity Demidovich mainly worked in five areas: dynamical systems with integral invariants; periodic and quasi-periodic solutions of ordinary differential equations; correct and it is correct (on Demidovich) differential system; limited solutions of ordinary differential equations; sustainability of ordinary differential equations, in particular, the orbital stability of dynamical systems. Along with scientific and educational activities in the MSU, BP Demidovich concurrently taught at several leading universities in Moscow (MVTU, NE Bauman, the Military Engineering Academy, F. E. Dzerzhinsky, etc.). His experience as a teacher is reflected in the books he wrote on mathematical analysis, that were translated into many foreign languages. Demidovich was often invited in Organizing Committees of scientific conferences and he actively cooperated with the editorial staff of various mathematical journal ("Differential Equations", RJ "Mathematics"), as well as the mathematical formulation of "BSE". References 1906 births 1977 deaths Soviet mathematicians Academic staff of Moscow State University