@article{DAN_1988_303_6_a6,
     author = {G. V. Radzievskii},
     title = {Completeness of derivative chains of polynomial pencils of},
     journal = {Doklady Akademii Nauk},
     pages = {1310--1315},
     year = {1988},
     volume = {303},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1988_303_6_a6/}
}