@article {35262,
	title = {The patterns of post-glacial spread of white spruce},
	volume = {13},
	year = {1986},
	pages = {527-540},
	publisher = {Journal of Biogeography},
	url = {http://www.jstor.org/stable/2844816?seq=4},
	author = {Ritchie, J.C. and MacDonald, G.M}
}
