from 1930 to 1940 n. g. chetaev was a professor of kazan university where he created a scientific school of the mathematical theory of stability of motion. the school consisted of thirty one of his doctoral students, direct followers and collaborators, among whom there are such prominent mathematicians as nikolay krasovsky and valentin rumyantsev. n. g. chetaev initiated the formation of department of aerodynamics at kazan university, on which base kazan aviation institute was founded in 1932. in 1939 he was conferred a degree of doctor of science in physics and mathematics. from 1940 to 1959 he held a position of full professor at moscow university. in 1940 n. g. chetaev organized and became a head of department of general mechanics at institute of mechanics of academy of sciences of ussr (on 21 november 1991 renamed into russian academy of sciences) that was opened in the same year. from 1945 to 1953 he was the director of the institute.