@mastersthesis {39521,
	title = {Systematics of North American Petasites (Asteraceae: Senecioneae)},
	volume = {Botany},
	year = {1994},
	pages = {249},
	address = {University of Alberta},
	url = {http://search.proquest.com/docview/304147799},
	author = {Cherniawsky, Donna Marie}
}
