@article{ISU_2011_11_3_a0,
     author = {M. I. Ismailov},
     title = {Hilbert generalizations $b${-Bessel} systems},
     journal = {Izvestiya of Saratov University. Mathematics. Mechanics. Informatics},
     pages = {3--10},
     publisher = {mathdoc},
     volume = {11},
     number = {3},
     year = {2011},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ISU_2011_11_3_a0/}
}