@article {37473,
	title = {Grassland ecosystems and climate change : hypotheses for the northern grassland-boreal forest ecotone. Proceedings of the Twelfth North American Prairie Conference, 1990},
	year = {1990},
	pages = {4},
	url = {http://images.library.wisc.edu/EcoNatRes/EFacs/NAPC/NAPC12/reference/econatres.napc12.aschwarz.pdf},
	author = {Schwarz, Arthur G. and Wein, Ross W.}
}
