Phil Archer. <a href="http://www.w3.org/TR/2007/NOTE-powder-use-cases-20071031"><cite>POWDER: Use Cases and Requirements.</cite></a> 31 October 2007. W3C Note. URL: <a href="http://www.w3.org/TR/2007/NOTE-powder-use-cases-20071031">http://www.w3.org/TR/2007/NOTE-powder-use-cases-20071031</a>