Discovery of a strong Baldwin effect in mid-infrared AGN linesS. F. Hönig, A. Smette, T. Beckert, H. Horst, W. Duschl, P. Gandhi, M. Kishimoto and G. WeigeltA&A, 485 2 (2008) L21-L24DOI: https://doi.org/10.1051/0004-6361:200810123