NIR spectroscopy of luminous infrared galaxies and the hydrogen recombination photon deficit J. R. Valdés, S. Berta, A. Bressan, A. Franceschini, D. Rigopoulou and G. Rodighiero A&A, 434 1 (2005) 149-161 Published online: 01 April 2005 DOI: 10.1051/0004-6361:20035831