@article{101977,
      url = {http://digitallibrary.un.org/record/101977},
      title = {International classification of coal /},
      publisher = {UN,},
      recid = {101977},
      pages = {11, 3 p. :},
      address = {Geneva :. 1984-11-27},
      year = {1984},
      month = {Nov},
}