@article {30479,
	title = {Monitoring air quality with lichens : a feasibility study},
	volume = {Environmental Research Monograph 1976-2},
	year = {1976},
	pages = {69},
	institution = {Syncrude Canada Ltd.},
	address = {Edmonton, AB},
	author = {Douglas, G. W. and Skorepa, A. C.}
}
