Thanks to Ulrike Krommer, Christian Freksa, Mark Ring, Christof Schmidhuber, Kurt Prelinger, Karolin Schmidhuber, Gerhard Weiss, Astrid Kiehn, Rohan Baxter, Margit Kinder, Martin Eldracher, Daniel Prelinger, Sepp Hochreiter, Gary Greenfield, and Charles Ames, for useful comments.