Renormalization of the quark mass matrix
  Using a set of rephasing-invariant variables, it is shown that the renormalization group equations for quark mixing parameters can be written in a form that is compact, in addition to having simple properties under flavor permutation. We also found approximate solutions to these equations if the quark masses are hierarchical or nearly degenerate. 
S. H. Chiu and T. K. Kuo
hep-ph