by Roche, G., Bystricky, J., Carroll, J., Gordon, J., Hallman, T., Igo, G., Kirk, P., Krebs, G.F., Landaud, G., Letessier-Selvon, A., Madansy, L., Matis, H.S., Miller, D., Naudet, C., Schroeder, L.S., Seidl, P.A., Wang, Z.F., Welsh, R., Yegneswaran, A.
Published in Physics letters. B (10.08.1989)