Near-threshold production of heavy quarks with QQbar_threshold
  We describe the QQbar_threshold library for computing the production cross section of heavy quark-antiquark pairs near threshold at electron-positron colliders. The prediction includes all presently known QCD, electroweak, Higgs, and nonresonant corrections in the combined nonrelativistic and weak-coupling expansion. 
M. Beneke, Y. Kiyo, A. Maier, J. Piclum
hep-ph