@book {6855,
	title = {Preserving Nature in the National Parks: A History},
	year = {1997},
	publisher = {Yale University Press},
	organization = {Yale University Press},
	address = {New Haven},
	keywords = {Conservation, National Park Service, Park development},
	url = {http://www.nps.gov/history/history/online_books/sellars/},
	author = {Sellars, Richard West}
}
