Conceptual Graphs Home Page - Features introductory material and bibliography, standard notation, events, projects, tools and researchers.
John Sowa on Knowledge Representation - Provides background material and tutorials on ontology and related topics in logic, conceptual graphs, and natural language semantics.
Knowledge Interchange Format (KIF) - A DARPA project. KIF is a language designed for use in the interchange of knowledge among disparate computer systems.
Knowledge Representation Resources - A list of knowledge representation resources, part of the AI Education Repository at the University of Southwestern Louisiana.
KR, Inc. - Charitable organization concerned with fostering research and communication on knowledge representation and reasoning. Features conferences, educational materials and mailing lists.
Tockit Project - Aims to create a framework for conceptual knowledge processing in terms of social structures and a common code base. Features software description and contact details.
WebKB - A set of tools using Conceptual Graphs formalism for building and documentation of knowledge bases, indexing or connecting elements of WWW-accessible documents.