title: Calculation of Atomic Elastic Scattering Cross Sections of
          Electrons and Positrons

   authors: Jiri Stepanek, Osvaldo Moreira

   affiliations: Paul Scherrer Institut (PSI), CH-5232 Villigen PSI,

   summary: Variationally optimized effective atomic potential is calc-
            ulated solving relativistic Dirac equations, whereas direct
           (or Hartree) part of the potential is obtained in a straight-
           forward way from the electron density. The "variationally
           optimum" exchange potential for bound electrons is calculated