@article{DE_1987_23_4_a10,
     author = {Yu. V. Pokornyi and K. P. Lazarev},
     title = {Some oscillation theorems for multipoint problems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {658--670},
     publisher = {mathdoc},
     volume = {23},
     number = {4},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1987_23_4_a10/}
}