@article{DAN_1971_200_5_a1,
     author = {W. Gerisch},
     title = {A remark on the work of {N.} {K.~Bari} on biorthogonal systems and bases in {Hilbert} space},
     journal = {Doklady Akademii Nauk},
     pages = {1018--1019},
     year = {1971},
     volume = {200},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1971_200_5_a1/}
}