@article{ZNSL_1996_235_a3,
     author = {A. V. Bolsinov and V. S. Matveev},
     title = {Singularities of momentum maps of integrable {Hamiltonian} systems with two degrees of freedom},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {54--86},
     publisher = {mathdoc},
     volume = {235},
     year = {1996},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1996_235_a3/}
}