1. and , Analysis of Toeplitz Operators (Akademie Verlag, Berlin, 1989).
2. and , Approximate Identities and Stability of Discrete Convolution Operators with Flip, Operator Theory: Advances and Applications Vol. 110 (Birkhäuser, Basel, 1999).
3. Splineapproximation für singuläre Integralgleichungen auf ebenen, glattberandeten Gebieten, Dissertation, Chemnitz University of Technology (1998) (in German).
4. and , Convolution Equations and Projection Methods of their Solution, Translations of Mathematical Monographs Vol. 41 (Amer. Math. Soc., Providence, RI, 1974).