[1] UNIV DORTMUND,INST EXPTL PHYS 4,D-4600 DORTMUND 50,FED REP GER
[2] UNIV GLASGOW,DEPT NAT PHILOSOPHY,GLASGOW G12 8QQ,SCOTLAND
[3] UNIV LONDON IMPERIAL COLL SCI & TECHNOL,DEPT PHYS,LONDON SW7 2AZ,ENGLAND
[4] MAX PLANCK INST PHYS & ASTROPHYS,D-8000 MUNICH 40,FED REP GER
[5] IST NAZL FIS NUCL,DEPARTIMENTO FIS,PISA,ITALY
[6] SCUOLA NORMALE SUPER,I-56100 PISA,ITALY
[7] IST NAZL FIS NUCL,TRIESTE,ITALY
[8] IST FIS,TRIESTE,ITALY
[9] UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706