I'm sure you seen this, but just in case...<div><br></div><div><a href="http://www.google.com.au/url?sa=t&source=web&cd=1&sqi=2&ved=0CBoQFjAA&url=http%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fdownload%3Fdoi%3D10.1.1.10.2998%26rep%3Drep1%26type%3Dpdf&ei=vdV5Ttj-FeTnmAWnu8mfAQ&usg=AFQjCNGmhN_q9dMWguJ4zAvXtQyf3beCZg&sig2=fKoE3-F7AbwU5A88UdD6Ow">http://www.google.com.au/url?sa=t&source=web&cd=1&sqi=2&ved=0CBoQFjAA&url=http%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fdownload%3Fdoi%3D10.1.1.10.2998%26rep%3Drep1%26type%3Dpdf&ei=vdV5Ttj-FeTnmAWnu8mfAQ&usg=AFQjCNGmhN_q9dMWguJ4zAvXtQyf3beCZg&sig2=fKoE3-F7AbwU5A88UdD6Ow</a></div>

<div><br></div><div>(Sorry for the Google tracking URL)</div><div><br></div><div>Phil</div>