%0 Journal Article %A V. S. Butylkin %A O. V. Kudrevatova %T Wave-function representation by means of a system of nonorthogonal functions and allowance for the contribution of the discrete levels of a single-particle system to the probability of its multiphoton ionization %J Teoretičeskaâ i matematičeskaâ fizika %D 1970 %P 154-158 %V 5 %N 1 %U http://geodesic.mathdoc.fr/item/TMF_1970_5_1_a14/ %G ru %F TMF_1970_5_1_a14