%0 Journal Article %A V. K. Saul'ev %T Refined methods and two-sided approximations to a solution of parabolic equations %J Doklady Akademii Nauk %D 1958 %P 1088-1090 %V 118 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1958_118_6_a9/ %G ru %F DAN_1958_118_6_a9