Search for a bound trineutron with the 3He(π-,π+)nnn reaction J. Gräter, P. A. Amaudruz, R. Bilger, P. Camerini, J. Clark, H. Clement, E. Friedman, L. Felawka, S.N. Filippov, E. Friagiacomo et al. (23 more) Eur. Phys. J. A, 4 1 (1999) 5-7 Published online: 15 January 1999 DOI: 10.1007/s100500050196