@article{ND_2014_10_4_a4,
     author = {Anatoly P. Markeev},
     title = {Simplifying the structure of the third and fourth degree forms in the expansion of the {Hamiltonian} with a linear transformation},
     journal = {Russian journal of nonlinear dynamics},
     pages = {447--464},
     publisher = {mathdoc},
     volume = {10},
     number = {4},
     year = {2014},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ND_2014_10_4_a4/}
}