@article{IVM_1996_6_a1,
     author = {F. N. Garif'yanov},
     title = {Transformations of biorthogonal systems, and some of their applications. {I.}},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {5--16},
     year = {1996},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1996_6_a1/}
}