[1] BAYLOR UNIV,INST ENVIRONM STUDIES,WACO,TX 76703
[2] RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND
[3] UNIV LECCE,DEPT PHYS,I-73100 LECCE,ITALY
[4] SERC,SWINDON SN2 1ET,ENGLAND
[5] EUROPEAN SPACE RES & TECHNOL CTR,EUROPEAN SPACE AGCY,DEPT SPACE SCI,2200 AG NOORDWIJK,NETHERLANDS
[6] MAX PLANCK INST NUCL PHYS,D-6900 HEIDELBERG 1,FED REP GER
[7] CALTECH,JET PROP LAB,PASADENA,CA 91109
[8] UNIV SHEFFIELD,DEPT PHYS,SHEFFIELD S3 7RH,S YORKSHIRE,ENGLAND
[9] TECH UNIV MUNICH,D-8000 MUNICH 2,FED REP GER
[10] MESSERSCHMITT BOLKOW BLOHM GMBH,DIV SPACE,D-8000 MUNICH 80,FED REP GER
[11] LUND OBSERV,INST ASTRON,S-22100 LUND,SWEDEN
[12] OFF NATL ETUD & RECH AEROSP,CTR ETUD RECW TOULOUSE,DEPT ETUD RECH & TECHNOL SPATIALE,F-31055 TOULOUSE,FRANCE
[13] UNIV BARI,DEPT PHYS,I-70124 BARI,ITALY
[14] UNIV WALES UNIV COLL CARDIFF,DEPT APPL MATH,CARDIFF CF1 1XL,S GLAM,WALES
[15] EUROPEAN SPACE OPERAT CTR,DIV ORBIT ALTITUDE,D-6100 DARMSTADT,FED REP GER