@book{282722,
	author = {United States.},
	title = {Issues regarding the new NPS methodology used to evaluate the achievement of natural quiet restoration standards in Grand Canyon National Park :},
	publisher = {U.S. Government Printing Office,},
	year = {1999 [i.e. 2000]},
	address = {Washington :},
	note = {"Serial no. 106-33."},
	url = {https://purl.access.gpo.gov/GPO/LPS4284}
}