@article{MZM_1997_61_2_a1,
     author = {B. S. Kruglikov},
     title = {Exact smooth classification of hamiltonian vector fields on two-dimensional manifolds},
     journal = {Matemati\v{c}eskie zametki},
     pages = {179--200},
     publisher = {mathdoc},
     volume = {61},
     number = {2},
     year = {1997},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1997_61_2_a1/}
}