@article {37914,
	title = {Evaluation of the sustainability of extensive annual cultivation within selected agroecological resource areas of Alberta},
	volume = {Land Resource Research Centre Contribution No. 91-18},
	year = {1991},
	pages = {95},
	institution = {Agriculture Canada, Alberta Agriculture},
	author = {Hiley, J. C. and Wehrhahn, Rhonda L.}
}
