%0 Journal Article %A S. I. Mitrokhin %T On the asymptotic behavior of the spectrum of a~sixth-order differential operator, whose potential is~the~delta function %J Žurnal Srednevolžskogo matematičeskogo obŝestva %D 2020 %P 280-305 %V 22 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/SVMO_2020_22_3_a2/ %G ru %F SVMO_2020_22_3_a2