RT Journal Article SR Electronic T1 The circle of Willis (1621–75) JF Journal of Neurology, Neurosurgery & Psychiatry JO J Neurol Neurosurg Psychiatry FD BMJ Publishing Group Ltd SP 86 OP 86 DO 10.1136/jnnp.69.1.86 VO 69 IS 1 A1 PEARCE, J M S YR 2000 UL http://jnnp.bmj.com/content/69/1/86.abstract AB