@article{DAN_1979_246_3_a2,
     author = {I. A. Vestfrid and A. Timan},
     title = {On a universal property of {Hilbert} spaces},
     journal = {Doklady Akademii Nauk},
     pages = {528--530},
     publisher = {mathdoc},
     volume = {246},
     number = {3},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_246_3_a2/}
}