%0 Journal Article %A P. E. Sobolevskii %T The use of fractional powers of self-adjoined operators in the investigation of some non-linear differential equations in Hilbert space %J Doklady Akademii Nauk %D 1960 %P 272-275 %V 130 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1960_130_2_a7/ %G ru %F DAN_1960_130_2_a7