@article{6218,
      author = {Zabetakis, Michael George,},
      url = {http://library.usi.edu/record/6218},
      title = {Coal mining /},
      publisher = {U.S. Dept. of the Interior, Mining Enforcement and Safety  Administration,},
      recid = {6218},
      pages = { [6], 34 p. :},
      address = {[Washington] :},
      year = {1975},
}