A subtraction scheme for computing QCD jet cross sections at NNLO:   regularization of doubly-real emissions
  We present a subtraction scheme for computing jet cross sections in electron-positron annihilation at next-to-next-to-leading order accuracy in perturbative QCD. In this first part we deal with the regularization of the doubly-real contribution to the NNLO correction. 
Gabor Somogyi, Zoltan Trocsanyi and Vittorio Del Duca