@article{SM_2015_206_5_a4,
     author = {E. A. Kudryavtseva and D. A. Fedoseev},
     title = {Mechanical systems with closed orbits on manifolds of revolution},
     journal = {Sbornik. Mathematics},
     pages = {718--737},
     publisher = {mathdoc},
     volume = {206},
     number = {5},
     year = {2015},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2015_206_5_a4/}
}