Numerical Solution of the Spinless Salpeter Equation by a Semianalytical   Matrix Method (a Mathematica 4.0 routine)
  In quantum theory, the so-called "spinless Salpeter equation," the relativistic generalization of the nonrelativistic Schroedinger equation, is used to describe both bound states of scalar particles and the spin-averaged spectra of bound states of fermions. A numerical procedure solves the spinless Salpeter equation by approximating this eigenvalue equation by a matrix eigenvalue problem with explicitly known matrices. 
Wolfgang Lucha and F. F. Schoberl