The knowledge representation system KL-ONE first appeared in 1977. Subsequently many systems based on the idea of KL-ONE have been built. The formal model-theoretic semantics which has been introduced for KL-ONE languages 9 provides means for investigating soundness and completeness of inference algorithms. It turned out that almost all implemented KL-ONE systems such as BACK, KL-TWO, LOOM, NIKL, SB-ONE use sound but incomplete algorithms.
/lp/association-for-computing-machinery/kris-knowledge-representation-and-inference-system-eOYm80JqE5