1. Dept. of Civil & Environ. Engineering, Univ. of California, Berkeley, CA 94720-1710
2. Dept. of Civil & Environ. Engineering, Brigham Young University, 368 CB, Provo, UT 84602
3. Dept. of Structural Engineering, Univ. of California, San Diego, La Jolla, CA 92093-0533
4. Faculty of Mathematics and Physical Sciences, Univ. of Chile, 2002 Blanco Encalada, Santiago Chile
5. Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Santiago, Chile
6. Department of Civil Engineering, University of Patras, 26500 Patras, Greece
7. School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta GA30332-0355
8. Dept. of Civil Engineering, Univ. of Concepción, Víctor Lamas 1290, Concepción, Chile
9. Dept. of Civil & Environ. Engineering, Univ. of Washington, Seattle, WA
10. Dept. of Civil & Environ. Engineering, Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801
11. USGS, Menlo Park, CA