Determination of the b-mass using renormalon cancellation
  Methods of Borel integration to calculate the binding ground energies and mass of b-barb quarkonia are presented. The methods take into account the leading infrared renormalon structure of the "soft" binding energy E(s) and of the quark pole masses mq, and the property that the contributions of these singularities in M(s) = 2 mq + E(s) cancel. 
Contreras H. Carlos