On Kropina Change of m-th Root Finsler Metrics
  In this paper, we consider Kropina change of $m$-th root Finsler metrics. We find necessary and sufficient condition under which the Kropina change of an $m$-th root Finsler metric be locally dually flat. Then we prove that the Kropina change of an $m$-th root Finsler metric is locally projectively flat if and only if it is locally Minkowskian. 
A. Tayebi, T. Tabatabaeifar and E. Peyghan
math.DG