Evaluating the geometric measure of multiparticle entanglement
  We present an analytical approach to evaluate the geometric measure of multiparticle entanglement for mixed quantum states. Our method allows the computation of this measure for a family of multiparticle states with a certain symmetry and delivers lower bounds on the measure for general states. It works for an arbitrary number of particles, for arbitrary classes of multiparticle entanglement, and can also be used to determine other entanglement measures. 
Lars Erik Buchholz, Tobias Moroder, Otfried G\"uhne
quant-ph