@article{9-790607-872070,
      recid = {255167},
      author = {Cravotta, Charles A.,},
      title = {Use of stable isotopes of carbon, nitrogen, and sulfur to  identify sources of nitrogen in surface waters in the lower  Susquehanna River Basin, Pennsylvania /},
      publisher = {U.S. Dept. of the Interior, U.S. Geological Survey ;},
      address = {[Reston, Va.] :},
      number = {9-790607-872070},
      pages = {v, 99 p. :},
      year = {1997},
      note = {"Prepared in cooperation with the Pennsylvania Department  of Environmental Protection, Bureau of Soil and Water  Conservation."},
      url = {http://library.usi.edu/record/255167},
}