Comparison of Exact Results for the Virtual Corrections to   Bremsstrahlung in Electron-Positron Annihilation at High Energies
  We have compared the virtual corrections to electron-positron annihilation to fermion pairs with single hard bremsstrahlung as calculated by S. Jadach, M. Melles, B.F.L. Ward and S.A. Yost to several other expressions. The most recent of these comparisons is to the leptonic tensor calculated by J.H. Kuhn and G. Rodrigo for radiative return. Agreement is found to within $10^{-5}$ or better, as a fraction of the Born cross section. 
S.A. Yost, C. Glosser, S. Jadach and B.F.L. Ward