A Shortcut to General Tree-level Scattering Amplitudes in N=4 SYM via   Integrability
  We combine recent applications of the two-dimensional quantum inverse scattering method to the scattering amplitude problem in four-dimensional N=4 Super Yang-Mills theory. Integrability allows us to obtain a general, explicit method for the derivation of the Yangian invariants relevant for tree-level scattering amplitudes in the N=4 model. 
Nils Kanning, Tomasz Lukowski, Matthias Staudacher
hep-th