@article{10355,
      recid = {10355},
      author = {Bertoldi, Michael J.},
      title = {Preliminary economics of mining a thick coal seam by  dragline, shovel-truck, and scraper mining systems /},
      publisher = {Dept. of the Interior,},
      address = {[Washington] :},
      pages = {[3], 27 p. :},
      year = {1977},
      url = {http://library.usi.edu/record/10355},
}