Hamiltonian nilpotent saddles of linear plus cubic homogeneous polynomial vector fields
In this paper, the authors completely characterize the global phase portraits in the Poincaré disk for all planar Hamiltonian vector fields with linear plus cubic homogeneous terms having a nilpotent saddle at the origin. To sum up, the method in this paper is technical and the result is interesting.
scientific article; zbMATH DE number 7446157