@article{DE_1998_34_4_a4,
     author = {Yu. F. Dolgii and S. G. Nikolaev},
     title = {Instability of a periodic system with delay},
     journal = {Differencialʹnye uravneni\^a},
     pages = {465--470},
     publisher = {mathdoc},
     volume = {34},
     number = {4},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1998_34_4_a4/}
}