@article{MZM_1970_8_6_a9,
     author = {I. V. Kamenev},
     title = {A criterion for the oscillation of solutions of second-order ordinary differential equations},
     journal = {Matemati\v{c}eskie zametki},
     pages = {773--776},
     publisher = {mathdoc},
     volume = {8},
     number = {6},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1970_8_6_a9/}
}