[1] Atkinson F V. Discrete and Continuous Boundary Problems. New York: Academic Press, 1964
[2] Dunford N, Schwartz J T. Linear Operators---Part II, Spectral Theory: Self-adjoint Operators in Hilbert Space. New York: Wiley-Interscience, 1963
[3] Kratz W. Quadratic Functionals in Variational Analysis and Control Theory. Berlin: Aka-demie Verlag GmbH, 1995
[4] Clark S, Gesztesy F. On Povzner-Wienholtz-type self-adjoineness results for matrix-valued Sturm-Liouville operators. Pro Roy Soc Edinburgh Sect A, 2003, 133(4): 747--758
[5] Everitt W N. On the limit point classification of second-order differential operators. J London Math Soc, 1966, 41: 531--534
[6] Everitt W N, Giertz M. On some properties of the domains of powers of certain differential operators. Proc London Math Soc, 1972, 24(3): 256--763
[7] Everitt W N, Giertz M, McLeod J B. On the strong and weak limit-point classification of second-order differential expressions. Proc London Math Soc, 1974, 29(3): 142--153
[8] Everitt W N, Hinton D B, Wong J S. On the SLP condition of ordinary differential equations of order 2n. Proc London Math Soc, 1974, 29(3): 351--357
[9] Hartman P. The number of L2-solutions of x''+p(t)x=0. Amer J Math, 1951, 73: 635--645
[10] Hinton D B, Shaw J K. Hamiltonian systems of limit point or limit circle type with both end points singular. J Differential Equations, 1983, 50: 444--464
[11] Krall A M. M(λ) theory for singular Hamiltonian systems with one singular point. SIAM J Math Anal, 1989, 20: 664--700
[12] Niessen H D, Zettl A. Singular Sturm-Liouville problems: the Friedrichs extension and comparison of eigenvalues. Proc London Math Soc, 1992, 64: 545--578
[13] Qi Jiangang, Chen Shaozhu. Strong limit-point classification of singular Hamiltonian expressions. Proc Amer Math Soc, 2004, 132: 1667--1674 |