Green Function for Spin 1/2 particle in a Coulomb + Scalar Potential
  We calculate the Green function for the Dirac equation describing a spin 1/2 particle in the presence of a potential which is a sum of the Coulomb potential V_C=-A_1/r and a Lorentz scalar potential V_S=-A_2/r. The bound state spectrum is obtained. 
Arvind Narayan Vaidya, Luiz Eduardo Silva Souza (Universidade Federal   do Rio de Janeiro)