@article{VMUMM_1984_4_a21,
     author = {A. S. Logachev},
     title = {Nondegeneracy of conditionally periodic motions of a heavy rigid body in the {Kovalevskaya} case},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {82--85},
     publisher = {mathdoc},
     number = {4},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1984_4_a21/}
}