Mark Baker; et al. <a href="http://www.w3.org/TR/2008/REC-xhtml-basic-20080729"><cite>XHTML&#8482; Basic 1.1.</cite></a> 29 July 2008. W3C Recommendation. URL: <a href="http://www.w3.org/TR/2008/REC-xhtml-basic-20080729">http://www.w3.org/TR/2008/REC-xhtml-basic-20080729</a>