@article{DE_1990_26_11_a4,
     author = {I. E. Vitrichenko},
     title = {Stability of the zero solution of a second-order nonlinear nonautonomous equation},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1878--1884},
     publisher = {mathdoc},
     volume = {26},
     number = {11},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1990_26_11_a4/}
}