Articles in Scholarly Journals [Incomplete List]

1. Eigenvalue asymptotics for an elliptic boundary problem
   Proceedings of the Royal Society of Edinburgh: Section A Mathematics, vol. 137, no. 02, p. 281, 2007
2. Proceedings of the American Mathematical Society, vol. 134, no. 10, pp. 2885–2894, 2006
3. Friedrichs extension and essential spectrum of systems of differential operators of mixed order
   Mathematische Nachrichten, vol. 278, no. 12-13, pp. 1591–1606, 2005
4. The essential spectrum of a model problem in 2-dimensional magnetohydrodynamics: a proof of a conjecture by J. Descloux and G. Geymonat
   Mathematische Nachrichten, vol. 269-270, no. 1, pp. 129–149, 2004
5. The essential spectrum of a system of singular ordinary differential operators of mixed order. Part III: A strongly singular case
   Mathematische Nachrichten, vol. 272, no. 1, pp. 104–112, 2004
6. Oscillation results for Sturm–Liouville problems with an indefinite weight function
   Journal of Computational and Applied Mathematics, vol. 171, no. 1-2, pp. 93–101, 2004
7. Singular Sturm?Liouville problems whose coefficients depend rationally on the eigenvalue parameter
   Journal of Mathematical Analysis and Applications, vol. 295, no. 1, pp. 258–275, 2004
8. Sturm–Liouville operators and their spectral functions
   Journal of Mathematical Analysis and Applications, vol. 282, no. 2, pp. 584–602, 2003
9. Mathematische Nachrichten, vol. 257, no. 1, pp. 16–35, 2003
10. Indefinite Sturm–Liouville problems
    Proceedings of the Royal Society of Edinburgh: Section A Mathematics, vol. 133, no. 03, p. 639, 2003
11. An elliptic boundary problem for a system involving a discontinuous weight
    manuscripta mathematica, vol. 108, no. 3, pp. 289–317, 2002
12. The Spectrum of a Parametrized Partial Differential Operator Occurring in Hydrodynamics
    Journal of the London Mathematical Society, vol. 65, no. 2, pp. 483–492, 2002
13. Quadratic and cubic transformations and zeros of hypergeometric polynomials
    Journal of Computational and Applied Mathematics, vol. 142, no. 2, pp. 411–417, 2002
14. Onn-Fold Expansions for Ordinary Differential Operators
    Mathematische Nachrichten, vol. 238, no. 1, pp. 62–77, 2002
15. Mathematische Nachrichten, vol. 238, no. 1, pp. 62–77, 2002
16. Zeros of the Hypergeometric Polynomials F(−n, b; −2n; z)
    Journal of Approximation Theory, vol. 110, no. 1, pp. 74–87, 2001
17. Compact perturbation of definite type spectra of self-adjoint quadratic operator pencils
    Integral Equations and Operator Theory, vol. 39, no. 2, pp. 127–152, 2001
18. On the essential spectrum of a differentially rotating star in the axisymmetric case
    Proceedings of the Royal Society of Edinburgh: Section A Mathematics, vol. 130, no. 01, p. 1, 2000
19. On the essential spectrum of the linearized Navier-Stokes operator
    Integral Equations and Operator Theory, vol. 38, no. 1, pp. 9–27, 2000
20. The Essential Spectrum of a System of Singular Ordinary Differential Operators of Mixed Order. Part II: The Generalization of Kako's Problem
    Mathematische Nachrichten, vol. 209, no. 1, pp. 55–81, 2000
21. Mathematische Nachrichten, vol. 209, no. 1, pp. 55–81, 2000
22. On the Essential Spectrum of a Differentially Rotating Star
    ZAMM, vol. 79, no. 11, pp. 739–755, 1999
23. The Essential Spectrum of a Non-Elliptic Boundary Value Problem
    Mathematische Nachrichten, vol. 178, no. 1, pp. 233–248, 1996
24. A Boundary Eigenvalue Problem for a System of Partial Differential Operators Occurring in Magnetohydrodynamics
    Mathematische Nachrichten, vol. 173, no. 1, pp. 141–167, 1995
25. Semi-boundedness of Ordinary Differential Operators
    Journal of Differential Equations, vol. 115, no. 1, pp. 24–49, 1995
26. Symmetrical Differential Operators and Their Friedrichs Extension
    Journal of Differential Equations, vol. 115, no. 1, pp. 50–69, 1995
27. Orthogonal Systems of Eigenvectors and Associated Vectors for Symmetric Holomorphic Operator Functions
    Mathematische Nachrichten, vol. 163, no. 1, pp. 45–64, 1993
28. An elliptic boundary value problem occurring in magnetohydrodynamics
    Manuscripta Mathematica, vol. 81, no. 1, pp. 387–412, 1993
29. Linearization of boundary eigenvalue problems
    Integral Equations and Operator Theory, vol. 14, no. 1, pp. 105–119, 1991
30. Equivalence of Differential-Boundary Eigenvalue Operators and their Characteristic Matrices
    Mathematische Nachrichten, vol. 141, no. 1, pp. 299–312, 1989
31. Necessary conditions for normal solvability in duals of LF-spaces
    Manuscripta Mathematica, vol. 58, no. 3, pp. 283–294, 1987
32. Equivalence of boundary eigenvalue operator functions and their characteristic matrix functions
    Mathematische Annalen, vol. 279, no. 2, pp. 267–275, 1987
33. Root functions of boundary eigenvalue operator functions
    Integral Equations and Operator Theory, vol. 9, no. 2, pp. 237–265, 1986
34. Root functions, eigenvectors, associated vectors and the inverse of a holomorphic operator function
    Archiv der Mathematik, vol. 42, no. 5, pp. 455–463, 1984