Spectral Theory, Mathematical System Theory, Evolution Equations, Differential and Difference Equations 21st International Workshop on Operator Theory and Applications, Berlin, July 2010 - Arendt, Wolfgang; Ball, Joseph A.; Behrndt, Jussi; Förster, Karl-Heinz; Mehrmann, Volker; Trunk, Carsten (Springer Basel : Imprint: Birkhäuser, 2012)