@article {585,
	title = {Pteridosperms are the backbone of seed-plant phylogeny},
	journal = {The Journal of the Torrey Botanical Society},
	volume = {133},
	year = {2006},
	pages = {119-168},
	chapter = {119},
	author = {Hilton, Jason and Bateman, R.M.}
}
@article {545,
	title = {Palaeobotanical systematic for the phylogenetic age: applying organ-species, form-species and phylogenetic species concepts in a framework of reconstructed fossil and extant whole-plants},
	journal = {Taxon},
	volume = {58},
	year = {2009},
	pages = {733-750},
	chapter = {733},
	author = {Bateman, R.M. and Hilton, J.}
}
