@book{129704,
	author = {Duhem, Pierre Maurice Marie, and Ariew, Roger. and ebrary, Inc.},
	title = {Medieval cosmology},
	publisher = {University of Chicago Press,},
	year = {1985.},
	address = {Chicago :},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10462228}
}