It is shown that a generally complex-valued function of a real variable is a solution of a classical SturmLiouville eigenvalue problem if and only if a related twoparameter eigenvalue problem for a ...

The study of inverse nodal problems in Sturm-Liouville theory is dedicated to the reconstruction of underlying potential functions and boundary conditions by utilising the nodal (zero-crossing) data ...

Spectral theory provides a rigorous framework for analysing the eigenvalues and eigenfunctions of differential operators that play an essential role in mathematical physics. In particular, ...