3dnd J = 4,5 autoionizing levels in Ca: laser optogalvanic spectroscopy and theoretical analysis S. Assimopoulos, A. Bolovinos, E. Luc-Koenig, S. Cohen, A. Lyras, P. Tsekeris and M. Aymar Eur. Phys. J. D, 1 3 (1998) 243-254 Published online: 15 March 1998 DOI: 10.1007/s100530050089