@article{DE_1982_18_2_a24, author = {M. M. Khapaev and I. V. Kuznetsova}, title = {Multifrequency systems that have lag}, journal = {Differencialʹnye uravneni\^a}, pages = {354--356}, publisher = {mathdoc}, volume = {18}, number = {2}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1982_18_2_a24/} }