%0 Journal Article %A O. V. Pochinka %T Necessary and sufficient conditions for topological classification of Morse--Smale cascades on 3-manifolds %J Russian journal of nonlinear dynamics %D 2011 %P 227-238 %V 7 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/ND_2011_7_2_a2/ %G ru %F ND_2011_7_2_a2