TY - JOUR AU - Anatoly P. Markeev TI - Simplifying the structure of the third and fourth degree forms in the expansion of the Hamiltonian with a linear transformation JO - Russian journal of nonlinear dynamics PY - 2014 SP - 447 EP - 464 VL - 10 IS - 4 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/ND_2014_10_4_a4/ LA - ru ID - ND_2014_10_4_a4 ER -