@article {39197,
	title = {Bison extirpation may have caused aspen expansion in western Canada},
	volume = {17},
	year = {1994},
	pages = {360-362},
	publisher = {Ecography},
	url = {http://www.blackwell-synergy.com/doi/abs/10.1111/Journal1600-0587.1992.tb00015.x},
	author = {Campbell, Celina and Campbell, Ian D. and Blyth, Charles B. and McAndrews, John H.}
}
