Postprint version. Published in Earthquake Spectra, Volume 21, Issue 1, February 1, 2005, pages 277-279.
Copyright 2005 Earthquake Engineering Research Institute. This article may be downloaded for personal use only. Any other use requires prior permission of the Earthquake Engineering Research Institute. The definitive version of this article is available at http://dx.doi.org/10.1193/1.1851547.
Civil and Environmental Engineering