Cavity ring-down spectroscopy of metallic gold nanoparticles S. Gilb, K. Hartl, A. Kartouzian, J. Peter, U. Heiz, H.-G. Boyen and P. Ziemann Eur. Phys. J. D, 45 3 (2007) 501-506 Published online: 27 June 2007 DOI: 10.1140/epjd/e2007-00211-9