@article{DAN_1981_259_6_a6,
     author = {A. Toraev},
     title = {On the oscillation of solutions of higher order equations of elliptic type},
     journal = {Doklady Akademii Nauk},
     pages = {1309--1311},
     publisher = {mathdoc},
     volume = {259},
     number = {6},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1981_259_6_a6/}
}