@article{DAN_1975_223_2_a6,
     author = {I. I. Ibragimov and N. I. Nagnibida},
     title = {On multiple completeness in the sense of {M.} {V.~Keldys} of a system of entire functions},
     journal = {Doklady Akademii Nauk},
     pages = {288--291},
     year = {1975},
     volume = {223},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1975_223_2_a6/}
}