@article{DAN_1962_145_6_a7,
     author = {A. Yu. Levin},
     title = {On the zero zone of stability},
     journal = {Doklady Akademii Nauk},
     pages = {1221--1223},
     year = {1962},
     volume = {145},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1962_145_6_a7/}
}