On Nakhleh's latest metric for phylogenetic networks
  We prove that Nakhleh's latest dissimilarity measure for phylogenetic networks is a metric on the classes of tree-child phylogenetic networks, of semi-binary time consistent tree-sibling phylogenetic networks, and of multi-labeled phylogenetic trees. We also prove that it distinguishes phylogenetic networks with different reduced versions. In this way, it becomes the dissimilarity measure for phylogenetic networks with the strongest separation power available so far. 
Gabriel Cardona, Merce Llabres, Francesc Rossello, Gabriel Valiente