Pontryagin, Lev Semyonovich[pontryahgin]
Mathematician, born in Moscow, Russia. The loss of his sight in an accident at the age of 14 did not prevent him from graduating from Moscow University, where he became professor in 1935. One of the leading Russian topologists, he worked on topological groups and their character theory, on duality in algebraic topology, and on differential equations with applications to optimal control. His book,Topological Groups (trans 1939), is still a standard work.