Infrared modified analysis for the $\tau$ lepton width
  We argue that accounting for higher order corrections in QCD by integrating a running coupling constant through an infrared region can be most easily done with making use of a scheme without the Landau pole. Within this approach the entire ambiguity of the answer is identical to that of the choice of renormalization scheme. The uncertainties for the $\tau$ lepton width resulting from such a technique are discussed. 
N.V.Krasnikov and A.A.Pivovarov