@book{21799,
	author = {Vilanova y Piera, Juan, and Espanya.},
	title = {Geología agrícola /},
	publisher = {Ministerio de Fomento,},
	year = {1879},
	address = {Madrid :},
	url = {http://bipadi.ub.edu/digital/collection/cienterra/id/14418}
}