%0 Journal Article %A O. A. Ladyzhenskaya %T Example of nonuniqueness in the Hopf class of weak solutions for the Navier--Stokes equations %J Izvestiya. Mathematics %D 1969 %P 229-236 %V 3 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/IM2_1969_3_1_a13/ %G en %F IM2_1969_3_1_a13