Influence of the helium autoionization structures on the single/double ionization signal L. A.A. Nikolopoulos, Takashi Nakajima and P. Lambropoulos Eur. Phys. J. D, 20 2 (2002) 297-304 Published online: 19 July 2002 DOI: 10.1140/epjd/e2002-00135-x