@article {Becker1875,
	title = {Die Korallen der Nattheimer Schichten},
	journal = {Palaeontographica},
	volume = {21},
	year = {1875},
	pages = {121{\textendash}164, pl. 36{\textendash}39},
	keywords = {BL, JS, RCBS, TIP},
	url = {http://archive.org/details/palaeontographic21cass},
	author = {Becker, Ewald}
}
