Non-Markovian spectral broadening in interacting continuous-wave atom lasers H. P. Breuer, D. Faller, B. Kappler and F. Petruccione Europhys. Lett., 54 1 (2001) 14-20 Published online: 01 December 2003 DOI: 10.1209/epl/i2001-00222-0