Viktor Vladimirovich Wagner, also Vagner (Russian: Виктор Владимирович Вагнер) (4 November 1908 – 15 August 1981) was a Russian mathematician, best known for his work in differential geometry and on semigroups.
Wagner was born in Saratov and studied at Moscow State University, where Veniamin Kagan was his advisor.
Moreover, he was also accorded that rarest of privileges in the USSR: permission to travel abroad.
"[1] Wagner is credited with noting that the collection of partial transformations on a set X forms a semigroup
"This simple unifying observation, which is nevertheless an important psychological hurdle, is attributed by Schein (1986) to V.V.