@article{102336,
      url = {http://digitallibrary.un.org/record/102336},
      title = {Technical progress in mechanization of roadway drivage in  coal and stone ; increase in the share of roadways driven  by heading machines /},
      publisher = {UN,},
      recid = {102336},
      pages = {4, 8 p. :},
      address = {Geneva :. 1983-12-07},
      year = {1983},
      month = {Dec},
}