Paper  bibtex   

@techreport{pardo_assessment_2011,
	address = {Newtown Square, PA},
	type = {General {Technical} {Report} {NRS}-80},
	title = {Assessment of nitrogen deposition effects and empirical critical loads of nitrogen for ecoregions of the {United} {States}},
	url = {http://purl.fdlp.gov/GPO/gpo61054},
	language = {English},
	urldate = {2023-07-04},
	institution = {U.S. Dept. of Agriculture, Forest Service, Northern Research Station},
	author = {Pardo, Linda H. and Robin-Abbott, M. J. (Molly J.) and Driscoll, Charles T. (Charles Thurston) and {United States. Forest Service. Northern Research Station.}},
	year = {2011},
	keywords = {Terrestrial Ecoregions (CEC 1997)},
}