Codimension 4 singularities on reflectionally symmetryc planar vector fields.
The paper deals with the topological classification of singularities of vector fields on the plane which are invariant under reflection with respect to a line. As it has been proved in previous papers, such a classification is necessary to determine the different topological types of singularities of vector fiels on R whose linear part is invariant under rotations. To get the classification we use normal form theory and the the blowing-up method.