Institute of Mathematics, Polish Academy of Sciences, P.O. Box 137, 00-950 Warszawa, Poland
Bibliografia
[1] G. Birkhoff and G.-C. Rota, Ordinary Differential Equations, Ginn-Blaisdell, Boston, 1962.
[2] R. Courant and D. Hilbert, Methods of Mathematical Physics, vol. 1, Interscience, New York, 1953.
[3] C. T. Fulton and S. Pruess, Eigenvalue and eigenfunction asymptotics for regular Sturm-Liouville problems, J. Math. Anal. Appl. 188 (1994), 297-340.
[4] T. Kato, Perturbation Theory for Linear Operators, Springer-Verlag, Berlin, 1966.
[5] B. M. Levitan and I. S. Sargsyan, Sturm-Liouville and Dirac Operators, Kluwer, Dordrecht, 1991.
[6] J. D. Pryce, Numerical Solution of Sturm-Liouville Problems, Clarendon Press, New York, 1993.
[7] M. H. Stone, Linear Transformations in Hilbert Space, American Mathematical Society, New York, 1932.