@article{RM_1988_43_1_a2,
     author = {A. D. Bruno},
     title = {The normal form of a {Hamiltonian} system},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {25--66},
     publisher = {mathdoc},
     volume = {43},
     number = {1},
     year = {1988},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1988_43_1_a2/}
}