Resummation at Large $Q$ and at Small $x$
  We propose a unified and simple viewpoint to various evolution equations appropriate in different kinematic regions. We show that the resummation technique reduces to the Altarelli-Parisi equation, if the transverse degrees of freedom of a parton are ignored, to the Balitskii-Fadin-Kuraev-Lipatov equation, if the momentum fraction of a parton vanishes, and to the Gribov-Levin-Ryskin equation, if the recombination of gluons is included. 
Hsiang-nan Li