Legendre F, Nel A, Svenson GJ, Robillard T, Pellens R, Grandcolas P (2015) Phylogeny of Dictyoptera: Dating the Origin of Cockroaches, Praying Mantises and Termites with Molecular Data and Controlled Fossil Evidence. PLoS ONE 10(7): e0130127. doi:10.1371/journal.pone.0130127

See the paper here: https://drive.google.com/file/d/0B_iJfIsJ4GB0anFZODhMekMxWU0/view?usp=sharing