The triple Higgs self-coupling at future e+e- colliders: a   signal-to-background study for the standard model
  The experimental reconstruction of the Higgs self-energy potential is essential to a verification of the Higgs boson's role in spontaneous electroweak symmetry breaking. The first step towards this goal, the measurement of the triple Higgs self-coupling, can possibly be accomplished at the next generation of linear colliders. Here we present a background study of the most promising channel, double Higgs-strahlung off a Z boson, e+e- -> HHZ, with the subsequent decay H -> b bbar, and evaluate the feasibility of its measurement. 
D.J. Miller and S. Moretti