David Booth; Canyang Kevin Liu. <a href="http://www.w3.org/TR/2007/REC-wsdl20-primer-20070626"><cite>Web Services Description Language (WSDL) Version 2.0 Part 0: Primer.</cite></a> 26 June 2007. W3C Recommendation. URL: <a href="http://www.w3.org/TR/2007/REC-wsdl20-primer-20070626">http://www.w3.org/TR/2007/REC-wsdl20-primer-20070626</a>