@article {Thorne:2002:0040-0262:511,
	author = "Thorne R.F.",
	title = "How many species of seed plants are there?",
	journal = "Taxon",
	volume = "51",
	number = "3",
	year = "2002",
	abstract = "",
	pages = "511-512",
	url = "http://www.ingentaconnect.com/content/iapt/tax/2002/00000051/00000003/art00009"
}