- Correspondence to: Dr E A Smith Department of Social and Behavioral Sciences, Box 0612, University of California, San Francisco, CA 94143, USA;
- Accepted July 28, 2005
- First published November 14, 2005.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.