On a Sturm-Liouville Type Problem with Retarded Argument
  In this work a Sturm-Liouville type problem with retarded argument which contains spectral parameter in the boundary conditions and with transmission conditions at the point of discontinuity are investigated. We obtained asymptotic formulas for the eigenvalues and eigenfunctions. 
Erdo\u{g}an \c{S}en, Azad Bayramov
math.CA