@article{DE_1970_6_3_a18,
     author = {Hoang Van Tao},
     title = {On the generalization of a certain theorem of {N.} {N.} {Bogoljubov} on averaging},
     journal = {Differencialʹnye uravneni\^a},
     pages = {555--557},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1970_6_3_a18/}
}