Equivalence of Morse-Smale flows on 4-manifolds

The paper concerns to the question of a topological classification of Morse-Smale flows with three critical points on closed 4-manifolds. One proves that if $f^t_1$, $f^t_2$ are Morse-Smale flows with the non-wandering set consisting of three points on closed 4-manifolds $M^4_1$, $M^4_2$ respectively, then $f^t_1$, $f^t_2$ are topologically equivalent.