\begin{thebibliography}{1}

\bibitem{AKSF83}
Janice~S. Aikins, John~C. Kunz, Edward~H. Shortliffe, and R.~J. Fallat.
\newblock Puff: An expert system for interpretation of pulmonary function data.
\newblock 16:199--208, 1983.

\bibitem{Barnett-j82}
Jeffrey~A. Barnett.
\newblock Some issues of control in expert systems.
\newblock In {\em Proceedings of the International Conference on Cybernetics
  and Society}, pages 1--5. IEEE, 1982.

\bibitem{Koton83}
Phyllis~A. Koton.
\newblock A system to aid in the solution of problems in molecular genetics.
\newblock Unpublished SM thesis, 1983.

\bibitem{Koton85a}
Phyllis~A. Koton.
\newblock Towards a problem solving system for molecular genetics.
\newblock Technical Report 338, May 1985.

\bibitem{SwartoutPhD}
William~R. Swartout.
\newblock Producing explanations and justifications of expert consulting
  programs.
\newblock Technical Report 251, January 1981.

\end{thebibliography}
