Determining the Coupling of a Higgs Boson to $ZZ$ at Linear Colliders
  We demonstrate that, at a 500 GeV e+e- collider, inclusion of the $ZZ$-fusion process for production of a light standard-model-like Higgs boson can substantially increase the precision with which the $ZZh$ coupling can be determined (using the model-independent recoil mass technique) as compared to employing only $Zh$ associated production. 
J.F. Gunion, T. Han and R. Sobey