Richard S. Westfall  is best known for his biography of a mathematician who was a key figure in what?
Richard S. Westfall Richard S. Westfall (April 22, 1924 – August 21, 1996) was an American academic, biographer and historian of science. He is best known for his biography of Isaac Newton and his work on the scientific revolution of the 17th century.
Jacques Hadamard Jacques Salomon Hadamard ForMemRS (] ; 8 December 1865 – 17 October 1963) was a French mathematician who made major contributions in number theory, complex function theory, differential geometry and partial differential equations.