Normal forms for perturbations of the Euler top / Heinz HanßmannQuasi-periodic motions of a rigid body : a case study on perturbations of superintegrable systems / Heinz HanßmannEquivariant perturbations of the Euler top / Heinz HanßmannQuasi-periodic motion of a rigid body under weak forces / Heinz HanßmannOn the Hamiltonian Hopf bifurcations in the 3D Hénon-Heiles family / by H. Hanßmann and J.C. van der MeerAlgebraic methods for determining Hamilton[ian] Hopf bifurcations in three-degree-of-freedom systems / by H. Hanßmann and J.C. van der MeerFunctionaalanalyse / Heinz Hanßmann