Spectrum and Spectral Singularities of a Quadratic Pencil of a Schrödinger Operator with Boundary Conditions Dependent on the Eigenparameter

Xiang ZHU, Zhao Wen ZHENG, Kun LI

Acta Mathematica Sinica . 2023, (11): 2164 -2180 . DOI: 10.1007/s10114-023-1413-6