1. An anomalous posterior cerebral artery
2. Microsurgical anatomy of the supraclinoid portion of the internal carotid artery
3. Gillilan, L.A. (1975) Anatomy and embryology of the arterial system of the brain stem and cerebellum; in Vinken, P.J., G.W. Bruyn (eds): Handbook of Clinical Neurology. Amsterdam, North Holland, vol 11.