%0 Journal Article %A M. I. Vishik %A V. V. Grushin %T On~a~class of higher order degenerate elliptic equations %J Sbornik. Mathematics %D 1969 %P 1-32 %V 8 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/SM_1969_8_1_a0/ %G en %F SM_1969_8_1_a0