@article{
  author = {khodadad kashi, farhad, nourani azad, samaneh, ghanbari, bahareh},
  title = {Impact of Fleet Renovation on the Productivity of Iran’s Road Transportation Industry},
  journal = {Economic  Modeling},
  year = {2018},
  volume = {12},
  number = {42},
  pages = {137-160},
  doi = {}
}