Continuous-wave Doppler-free two-photon spectroscopy of the 4d105s 2S1/2 → 4d95s2 2D3/2 transition in atomic silverT. Badr, M. D. Plimmer, P. Juncar, M. E. Himbert, J. D. Silver and G. D. RoveraEur. Phys. J. D, 31 1 (2004) 3-10DOI: https://doi.org/10.1140/epjd/e2004-00118-y