[1] STATE UNIV GRONINGEN,DEPT CHEM PHYS,9747 AG GRONINGEN,NETHERLANDS
[2] STATE UNIV GRONINGEN,CTR MAT SCI,DEPT APPL & SOLID STATE PHYS,9747 AG GRONINGEN,NETHERLANDS
[3] IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011
[4] IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011
[5] MAX PLANCK INST FESTKORPERFORSCH,HOCHFELD MAGNET LAB,F-91405 ORSAY,FRANCE