@book {2001,
	title = { Papal Letters in the Early Middle Ages},
	series = {History of Medieval Canon Law},
	number = {2},
	year = {2001},
	publisher = {The Catholic University Press},
	organization = {The Catholic University Press},
	address = {Washington (D.C.)},
	isbn = {9780813209197},
	author = {Fuhrmann, Horst}
}
