Amplification process in a laser injected by a narrow band weak signal S. Blin, G. M. Stéphan, R. Gabet, P. Besnard and D. Kilper Europhys. Lett., 52 1 (2000) 60-65 Published online: 01 September 2002 DOI: 10.1209/epl/i2000-00404-8