The QCD scattering amplitude from area behaved Wilson loops
  We explicitly construct the dominant saddle-point trajectory in the sum-over-path representation of meson scattering amplitudes in large $N$ QCD for area-behaved Wilson loops and show that it dominates in the Regge regime. The graphic representation of the leading trajectory is very similar to the diagrams widely used to illustrate meson scattering. 
Y. Makeenko and P. Olesen
hep-th hep-ph