\bibitem{kwg}
M.M. Kellog, H.R. Wills, and P.H. Goodman.
\newblock A biologically realistic computer model of neocortical associative
  learning for the study of aging and dementia.
\newblock {\em J. Investig. Med.}, {\bf 47}(2), February 1999.

\bibitem{wkg}
H.R. Wills, M.M. Kellogg, and P.H. Goodman.
\newblock Cumulative synaptic loss in aging and alzheimer's dementia: A
  biologically realistic computer model.
\newblock {\em J. Investig. Med.}, {\bf 47}(2), February 1999.