In memoriam: Herbert Stahl August 3, 1942-April 22, 2013

After a prolonged and arduous fight with cancer, our beloved Herbert Robert Stahl1 died in his 71st year on April 22, 2013, in Berlin. Herbert was born on August 3, 1942, in Fehl-Ritzhausen, in the German state of RheinlandPfalz. At the age of 16, he started to work as an electrician for Allgemeine ElektricitätsGesellschaft (AEG, General Electricity Company), and by the time of his retirement in 2008 he established himself as one of the most prominent, respected, and honored mathematicians in approximation theory, orthogonal polynomials, and related fields. Before his university education, after working at AEG in 1958–1964, he became a sailor for a short time. His undergraduate, graduate, and postgraduate studies were all done at the Technische Universität Berlin (TUB) in the period 1965–1974. His Ph.D. (Dr. rer. nat.) dissertation in 1974, written under the supervision of Christian Pommerenke, was titled “Contributions to the convergence problem of Padé approximants”. Eventually he became an expert on Padé approximation, but his interest was wider, it included function theory, complex approximation, rational approximation, approximation with varying weights, and orthogonal polynomials. He obtained