@article {570,
	title = {New coniferophytes ovulate structures from the Early Permian of China},
	journal = {Botanical Journal of the Linnean Society},
	volume = {129},
	year = {1999},
	pages = {115-138},
	chapter = {115},
	author = {Geng, Baoyin and Hilton, Jason}
}
@article {489,
	title = {Batenburgia sakmarica Hilton et Geng, gen. et sp. nov., a new genus of conifer from the Lower Permian of China},
	journal = {Review of Palaeobotany and Palynology},
	volume = {103},
	year = {1998},
	pages = {263-287},
	chapter = {263},
	author = {Hilton, Jason and Geng, Baoyin}
}
