@conference {11809,
	title = {A Study of Ambient Air Quality and Visibility in National Parks},
	booktitle = {2nd Conference on Scientific Research in the National Parks},
	year = {1979},
	month = {November 26-30},
	pages = {130},
	publisher = {Virginia Polytechnic Institute},
	organization = {Virginia Polytechnic Institute},
	keywords = {Air quality, Flora, Vegetation monitoring},
	author = {Stephens, N. Thomas and Larson, Gary L and Albee, Thomas F}
}
