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\bibitem[Caminiti \bgroup \em et al.~\egroup  1990]{cami90}
Caminiti R., Johnson P.~B., Urbano A., 1990,
\newblock Making arm movements within different parts of space: Dynamic aspects
  in the primate motor cortex,
\newblock {\em J. Neuroscience}, 10(7):2039--2058.

\bibitem[Georgopoulos \bgroup \em et al.~\egroup  1982]{geor82}
Georgopoulos A.~P., Kalaska J.~F., Caminiti R., Massey J.~T., 1982,
\newblock On the relations between the direction of two-dimensional arm
  movements and cell discharge in primate motor cortex,
\newblock {\em J. Neurosci.}, 2(11):1527--1537.

\bibitem[Georgopoulos \bgroup \em et al.~\egroup  1988]{geor88}
Georgopoulos A.~P., Kettner R.~E., Schwartz A.~B., 1988,
\newblock Primate motor cortex and free arm movements to visual targets in
  three-dimensional space. {II.} {Coding} of the direction of movement by a
  neuronal population,
\newblock {\em J. Neurosci}, 8(8):2928--2937.

\bibitem[Kalaska and Crammond 1992]{kala92}
Kalaska J.~F., Crammond D.~J., 1992,
\newblock Cerebral cortical mechanisms of reaching movements,
\newblock {\em Science}, 255:1517--1523.

\bibitem[Kettner \bgroup \em et al.~\egroup  1988]{kett88}
Kettner R.~E., Schwartz A.~B., Georgopoulos A.~P., 1988,
\newblock Primate motor cortex and free arm movements to visual targets in
  three-dimensional space. {III.} {Positional} gradients and population coding
  of movement direction from various movement origins,
\newblock {\em J. Neurosci.}, 8(8):2938--2947.

\bibitem[Mussa-Ivaldi 1988]{muss88}
Mussa-Ivaldi F.~A., 1988,
\newblock Do neurons in the motor cortex encode movement direction? {An}
  alternative hypothesis,
\newblock {\em Neurosci. Lett.}, 91:106--111.

\bibitem[Poggio and Girosi 1990]{pogg90}
Poggio T., Girosi F., 1990,
\newblock Regularization algorithms for learning that are equivalent to
  multilayer networks,
\newblock {\em Science}, 247:978--982.

\bibitem[Schwartz \bgroup \em et al.~\egroup  1988]{schw88}
Schwartz A.~B., Kettner R.~E., Georgopoulos A.~P., 1988,
\newblock Primate motor cortex and free arm movements to visual targets in
  three-dimensional space. {I.} {Relations} between single cell discharge and
  direction of movement,
\newblock {\em J. Neurosci}, 8(8):2913--2927.

\end{thebibliography}