Recommended Citation
Postprint version. Published in Proceedings of the National Academy of Sciences of the United States of America, Volume 105, Issue 50, December 16, 2008.
Page E109. Copyright © 2008 by The National Academy of Sciences of the USA.
The definitive version is available at http://dx.doi.org/10.1073/pnas.0808976106.
Disciplines
Social and Behavioral Sciences
URL: http://digitalcommons.calpoly.edu/ssci_fac/31