[1] NIEMAN INST,DALLAS,TX 75205
[2] NORTHEASTERN UNIV,PHYS DEPT,BOSTON,MA 02115
[3] STEVENS INST TECHNOL,DEPT PHYS,HOBOKEN,NJ 07030
[4] MIT,FRANCIS BITTER NATL MAGNET LAB,CAMBRIDGE,MA 02139
[5] MIT,PHYS DEPT,CAMBRIDGE,MA 02139
[6] STEVENS INST TECHNOL,CRYOGENICS CTR,HOBOKEN,NJ 07030