Note on Permutation Sum of Color-ordered Gluon Amplitudes
  In this note we show that under BCFW-deformation the large z behavior of permutation sum of color-ordered gluon amplitudes found by Boels and Isermann in arxiv:1109.5888 can be simply understood from the well known Kleiss-Kuijf relation and Bern-Carrasco-Johansson relation. 
Yi-jian Du, Bo Feng and Chih-Hao Fu
hep-th hep-ph