%0 Journal Article %A Teresa RegiƄska %T Approximation of eigenvalues of nonselfadjoint problems on an infinite interval %J Mathematica Applicanda %D 1979 %P 71-77 %V 7 %N 14 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.14708/ma.v7i14.1432/ %R 10.14708/ma.v7i14.1432 %G pl %F 10_14708_ma_v7i14_1432