@article{227616,
      author = {Halvorson, William L. and Davis, Gary E.},
      url = {http://library.usi.edu/record/227616},
      title = {Science and ecosystem management in the national parks /},
      publisher = {University of Arizona Press,},
      recid = {227616},
      pages = {xii, 364 p. :},
      address = {Tucson :},
      year = {1996},
}