Joachim Nitsche

Joachim A. Nitsche (September 2, 1926, Nossen – January 12, 1996) was a German mathematician and professor of mathematics in Freiburg, known for his important contributions to the mathematical and numerical analysis of partial differential equations. The duality argument for estimating the error of the finite element method and a scheme for the weak enforcement of Dirichlet boundary conditions for Poisson's equation bear his name. Provided by Wikipedia