On the Multiple Spectrum of a Problem for the Bessel Equation of an Integer Order with Squared Spectral Parameter in the Boundary Condition.

The problem for the Bessel equation of an integer order with complex physical and spectral parameters in the boundary condition is considered. The spectral parameter enters the boundary condition quadratically. The question of the basis property of the system of eigenfunctions in the case of the appearance of a multiple eigenvalue is studied. [ABSTRACT FROM AUTHOR]