@article{DAN_1968_180_2_a1,
     author = {M. M. Belova},
     title = {Bounded solutions of systems of second order ordinary differential equations},
     journal = {Doklady Akademii Nauk},
     pages = {266--268},
     publisher = {mathdoc},
     volume = {180},
     number = {2},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1968_180_2_a1/}
}