| 1991 | The Feasibility of Defeat in Defeasible Reasoning. | Gerard Vreeswijk |
| 1991 | A Metalinguistic Treatment of Epistemic Contexts. | Paul Schweizer |
| 1991 | Assertional Default Theories: A Semantical View. | Torsten Schaub |
| 1991 | A Nonmonotonic Assumption-Based TMS Using Stable Bases. | William L. Rodi, Stephen G. Pimentel |
| 1991 | Implemented Knowledge Representation and Reasoning Systems: An Endangered Species? | Charles Rich |
| 1991 | Modeling Rational Agents within a BDI-Architecture. | Anand S. Rao, Michael P. Georgeff |
| 1991 | The Utility of Consistency-Based Diagnostic Techniques. | Gregory M. Provan, David L. Poole |
| 1991 | The Logic of Epistemic Inconsistency. | Tarcisio H. C. Pequeno, Arthur Buchsbaum |
| 1991 | A Theory of Inferred Causation. | Judea Pearl, Thomas Verma |
| 1991 | Generalizing Atoms in Constraint Logic. | C. David Page Jr., Alan M. Frisch |
| 1991 | Belief Revision and Default Reasoning: Syntax-Based Approaches. | Bernhard Nebel |
| 1991 | Universal Attachment: An Integration Method for Logic Hybrids. | Karen L. Myers |
| 1991 | Panel: Achieving Large Scale Knowledge Sharing. | William Mark |
| 1991 | Modal Nonmonotonic Logics: Ranges, Characterization, Computation. | V. Wiktor Marek, Grigori F. Shvarts, Miroslaw Truszczynski |
| 1991 | Toward a Metatheory of Action. | Vladimir Lifschitz |
| 1991 | S4 as the Conditional Logic of Nonmonotonicity. | Philippe Lamarre |
| 1991 | On the Relation between Explicit and Implicit Belief. | Gerhard Lakemeyer |
| 1991 | A Formal Theory of Spatial Reasoning. | Stephen G. Kaufman |
| 1991 | On the Difference between Updating a Knowledge Base and Revising It. | Hirofumi Katsuno, Alberto O. Mendelzon |
| 1991 | Qualifying Number Restrictions in Concept Languages. | Bernhard Hollunder, Franz Baader |
| 1991 | Model Checking vs. Theorem Proving: A Manifesto. | Joseph Y. Halpern, Moshe Y. Vardi |
| 1991 | A Temporal Probability Logic for Representing Actions. | Peter Haddawy |
| 1991 | The Role of Common Ontology in Achieving Sharable, Reusable Knowledge Bases. | Thomas R. Gruber |
| 1991 | Naming and Identity in a Multi-Agent Epistemic Logic. | Adam J. Grove, Joseph Y. Halpern |
| 1991 | Generalizing Prioritization. | Benjamin N. Grosof |