@article{MM_1995_7_5_a31,
     author = {V. S. Mokeichev},
     title = {Existence of non-zero periodic solution of differential equations},
     journal = {Matemati\v{c}eskoe modelirovanie},
     pages = {58},
     publisher = {mathdoc},
     volume = {7},
     number = {5},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MM_1995_7_5_a31/}
}