1. 1994, ISO 10303-203, Industrial Automation Systems and Integration—Product Data Representation and Exchange—Part 203: Application Protocol: Configuration Controlled 3D Design of Mechanical Parts and Assemblies.
2. 2008, STEP PDM Schema, http://www.wikistep.org/index.php/PDM_Usage_Guide
3. Information Models for Product Representation: Core and Assembly Models;Sudarsan;International Journal of Product Development
4. 2005, Web Ontology Language (OWL), http://www.w3.org/2004/OWL/
5. 2004, SWRL, W3C Member Submission, http://www.w3.org/Submission/SWRL/