Walter Haug, Versuch über die zyklische Idee des Prosa-«Lancelot», Cyclification. The Development of narrative cycles in the Chansons de Geste and the Arthurian Romances. [Proceedings of the Colloquium, Amsterdam, 17-18 Dec 1992], Koninklijke Nederlandse Adad. van Wetenschappen, 159, Amsterdam; Oxford, 1994 : p. 210 - 214