@article{102421,
      url = {http://digitallibrary.un.org/record/102421},
      title = {Drivage, development and support of roadways and faces in  deep mines and in difficult mining and atmospheric  conditions /},
      publisher = {UN,},
      recid = {102421},
      pages = {3 p.},
      address = {Geneva :. 1984-03-23},
      year = {1984},
      month = {Mar},
}