S. Salloway and R. Pratt.
  <b>A comparison of the cognitive benefits of donepezil in
  patients with cortical versus subcortical vascular dementia: A subanalysis of
  two 24-week, randomized, double-blind, placebo-controlled trials</b>.
  <i>Neurology</i>, 60(A):141-2, April 2003.<br />