[1] CORNELL UNIV,SCH MECH & AEROSP ENGN,ITHACA,NY 14853
[2] MCMASTER UNIV,DEPT MAT SCI & ENGN,HAMILTON L8S 4L7,ONTARIO,CANADA
[3] UNIV NANCY,ECOLE MINES,LMPSM,F-54042 NANCY,FRANCE
[4] MIT,DEPT MAT SCI & ENGN,CAMBRIDGE,MA 02139
[5] UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY,CA 94720