Reserves In the Coming Decade" -mentioned in a speech delivered before the International Mining Indaba in South Africa, yesterday.
http://www.miningweekly.com/article/david-hale-2011-02-09
As an aside,, David Hale, who happens to be based in Chicago, delivered a similar speech before the bi-annual Chicago Natural Resources Conference last November. I was fortunate enough to attend that conference. Hale is a widely respected & independent world economist