@article{IVM_1968_10_a1,
     author = {YU. P. Bychkov},
     title = {Some aspects of analytical dynamics in grouped variables},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {13--16},
     publisher = {mathdoc},
     number = {10},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1968_10_a1/}
}