Leech-Wilkinson, Daniel. 1990. Ars Antiqua - Ars Nova - Ars Subtilior. Man and Music I: Antiquity and the Middle Ages, edited by Daniel Leech-Wilkinson,  London: Macmillan-Granada.

Long, Michael P. 1990. Trecento Italy. Antiquity and the Middle Ages: From Ancient Greece to the 15th Century, edited by Michael P. Long, 241–68. Englewood Cliffs, New Jersey: Prentice Hall.