@article{9-790607-872070, note = {"Prepared in cooperation with the Pennsylvania Department of Environmental Protection, Bureau of Soil and Water Conservation."}, author = {Cravotta, Charles A.,}, url = {http://library.usi.edu/record/255167}, 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 ;}, number = {9-790607-872070}, recid = {255167}, pages = {v, 99 p. :}, address = {[Reston, Va.] :}, year = {1997}, }