@article{VSGU_2017_1_a4,
     author = {M. V. Shamolin},
     title = {Cases of integrability corresponding to the pendulum motion in four-dimensional space},
     journal = {Vestnik Samarskogo universiteta. Estestvennonau\v{c}na\^a seri\^a},
     pages = {41--58},
     publisher = {mathdoc},
     number = {1},
     year = {2017},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VSGU_2017_1_a4/}
}