L (λ)= λnAn+ λn− 1An− 1+···+ A0,(1) where the Ak are operators acting in a Hilbert space
and λ∈ C is the spectral parameter. In the simplest case L (λ)= λI− A, where I is the identity …

In this paper, the linear differential expression of order n≥ 2 n ≥ 2 with distribution
coefficients of various singularity orders is considered. We obtain the associated matrix for …

This paper is concerned with inverse spectral problems for higher-order (n> 2) ordinary
differential operators. We develop an approach to the reconstruction from the spectral data …

In this paper, we propose an approach to inverse spectral problems for the n-th order (n≥ 2)
ordinary differential operators with distribution coefficients. The inverse problems which …

Motivated by the study of certain nonlinear wave equations (in particular, the Camassa–
Holm equation), we introduce a new class of generalized indefinite strings associated with …

The paper deals with a new type of inverse spectral problems for second‐order quadratic
differential pencils when one of the boundary conditions involves arbitrary entire functions of …

An inverse spectral problem for the Sturm-Liouville operator with a singular potential from
the class $ W_2^{-1} $ is solved by the method of spectral mappings. We prove the …

In this paper, we for the first time prove local solvability and stability of the inverse Sturm‐
Liouville problem with complex‐valued singular potential and with polynomials of the …

This paper deals with second-order differential pencils with a fixed frozen argument on a
finite interval. We obtain the trace formulae under four boundary conditions: Dirichlet …

In this paper we study the inverse spectral problem of reconstructing energy-dependent
Sturm–Liouville equations from two spectra. We give a reconstruction algorithm and …