“…Specifically, the authors optimized the measurements to reveal the properties of the vacancy sharing process between the L subshells (Sarkadi and Mukoyama 1981). The complete process of the direct Coulomb ionization and the subsequent vacancy sharing cannot be described by first-order perturbation approaches, and it still represents a challenge for the theory in spite of the encouraging results achieved in numerous theoretical investigations (Sarkadi and Mukoyama 1981,1984,1990, Finck et a1 1983, Kocbach 1984, Spies et al 1984, Becker 1985, Berinde et a1 1985b, Sarkadi and Papp 1985, Sarkadi 1986a, b, 1989, Amundsen and Jakubassa-Amundsen 1988, Legrand et a1 1989, Trautmann and Baur 1989.…”