@book {2007,
	title = {The Interdict in the Thirteenth Century. A Question of Collective Guilt},
	year = {2007},
	pages = {300},
	publisher = {Oxford University Press},
	organization = {Oxford University Press},
	address = {Oxford},
	isbn = {978-0-19-920860-9},
	author = {Clarke, Peter D.}
}
