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Bao, Q., Sun, J., Hao, X. and Zettl, A. (2019) Characterization of Self-Adjoint Domains for Regular Even Order C-Symmetric Differential Operators. Electronic Journal of Qualitative Theory of differential Equations, 1-17.
https://doi.org/10.14232/ejqtde.2019.1.62

has been cited by the following article:

• TITLE: On the Spectra of General Ordinary Quasi-Differential Operators and Their L2w-Solutions

  AUTHORS: Sobhy El-Sayed Ibrahim

  KEYWORDS: General Ordinary Quasi-Differential Expressions, Regular and Singular End-Points, Singular Differential Operators, Essential Spectra, Point Spectra and Regularity Fields

  JOURNAL NAME: Advances in Pure Mathematics, Vol.12 No.3, March 21, 2022

  ABSTRACT: In this paper, we consider the general ordinary quasi-differential expression τ of order n with complex coefficients and its formal adjoint τ+ on the interval [a,b). We shall show in the case of one singular end-point and under suitable conditions that all solutions of a general ordinary quasi-differential equation are in the weighted Hilbert space provided that all solutions of the equations and its adjoint are in . Also, a number of results concerning the location of the point spectra and regularity fields of the operators generated by such expressions may be obtained. Some of these results are extensions or generalizations of those in the symmetric case, while the others are new.