Spectral problems in inhomogeneous media, spectral parameter power   series and transmutation operators
  We give a brief overview of recent developments in Sturm-Liouville theory concerning operators of transmutation (transformation) and spectral parameter power series (SPPS) and propose a new method for numerical solution of corresponding spectral problems. 
Vladislav V. Kravchenko and Sergii M. Torba
math.CA math-ph math.MP math.NA