1. RDF Primer. W3C Recommendation (10 February 2004), http://www.w3.org/TR/rdf-primer/
2. RDFQL database command reference. http://www.intellidimension.com/pages/rdfgateway/reference/db/default.rsp
3. SPARQL Query Language for RDF. W3C Working Draft (4 October 2006), http://www.w3.org/TR/2006/WD-rdf-sparql-query-20061004/
4. User guide for Sesame. Updated for Sesame release 1.2.3. http://www.openrdf.org/doc/sesame/users/index.html
5. WordNet, a lexical database for the English language. http://wordnet.princeton.edu/