Georg Friedrich Bernhard Riemann, was born on September 17, 1826, and died on July 20, 1866.
He was one of the most influential German mathematicians in the 19th century. He developed the subjects of partial differential equations, complex variable theory, differential geometry, analytic number theory, and laid the foundations for modern topology.
His paper "Uber die Hypothesen, Welche der Geometrie zu Grunde liegen" (In the hypotheses lying to the foundation of Geometry), presented in 1854, became a classic of mathematics, and its results were incorporated into Albert EINSTEIN's relativistic theory of gravitation.
Monastyrsky, Michael, Riemann, Topology, and Physics, trans. by James and Victoria King (1987)