MS Versus Pole Masses of Gauge Bosons II: Two-Loop Electroweak Fermion   Corrections
  We have calculated the fermion contributions to the shift of the position of the poles of the massive gauge boson propagators at two-loop order in the Standard Model. Together with the bosonic contributions calculated previously the full two-loop corrections are available. This allows us to investigate the full correction in the relationship between MS and pole masses of the vector bosons Z and W. Two-loop renormalization and the corresponding renormalization group equations are discussed. Analytical results for the master-integrals appearing in the massless fermion contributions are given. A new approach of summing multiple binomial sums has been developed. 
F.Jegerlehner (DESY, Zeuthen), M.Yu.Kalmykov (DESY, Zeuthen & Dubna,   JINR), O.Veretin (Karlsruhe U., ITT)