@article{40447,
      recid = {40447},
      author = {Case, Richard B.},
      title = {Small water purification systems /},
      publisher = {U.S. Dept. of the Interior, Bureau of Land Management:},
      address = {Denver, Colo. :},
      pages = {29 p. :},
      year = {1981},
      note = {Periodic updating anticipated.},
      url = {http://library.usi.edu/record/40447},
}