Master integrals for the two-loop penguin contribution in non-leptonic   B-decays
  We compute the master integrals that arise in the calculation of the leading penguin amplitudes in non-leptonic B-decays at two-loop order. The application of differential equations in a canonical basis enables us to give analytic results for all master integrals in terms of iterated integrals with rational weight functions. It is the first application of this method to the case of two different internal masses. 
Guido Bell, Tobias Huber
hep-ph