1. Adleman, L. and Blum, M., “Inductive Inference and Unsolvability”, Technical Report, Dept. Electrical Engineering and Computer Science and the Electronics Research Lab., U. Calif. at Berkeley, 1975.
2. “On the Automatic Formation of a Computer Program which represents a Theory”;Amarel,1962
3. “On Representations of Problems of Reasoning about Actions”;Amarel,1968
4. “Representations and Modeling in Problems of Program Formation”;Amarel,1971
5. Amarel, s., “Problems of Representation in Heuristic Problem Solving; Related Issues in the Development of Expert Systems”, Technical Report CBM-TR-118, Department of Computer Science, Rutgers University, February 1981, (To be published in Methods of Heuristics, Groner, Groner and Bischof, Eds., Lawrence Erlbaum Associates, Hillsdale, N.J.).