@article{IVM_1969_1_a15,
     author = {S. A. Agahanov and G. I. Natanson},
     title = {Letter to the editors},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {109--110},
     publisher = {mathdoc},
     number = {1},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1969_1_a15/}
}