Color flows for the process gg --> Bc + c + b-bar
  The contributions of different color flows into the gluonic Bc-meson production cross section has been calculated. This study is essential to simulate Bc-meson production with the help of Pythia program. The essence of matter is that in the frame work of the Lund model used by Pythia the hadronization way of the final partons and hadronic remnants depends on the color flow type. The modified method for calculation of the color flow contributions has been proposed. 
A. V. Berezhnoy