Weyl-Titchmarsh type formula for Hermite operator with small perturbation
Weyl-Titchmarsh type formula for periodic Schroedinger operator with Wigner-von Neumann potential
When is a non-self-adjoint Hill operator a spectral operator of scalar type?
Whittaker-Hill equation and semifinite-gap Schroedinger operators
Wolf-Keller theorem for Neumann eigenvalues