@article{DAN_1991_317_5_a6,
     author = {A. A. Martynyuk},
     title = {Boundedness of solutions of nonlinear systems with small},
     journal = {Doklady Akademii Nauk},
     pages = {1055--1058},
     publisher = {mathdoc},
     volume = {317},
     number = {5},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_317_5_a6/}
}