@article{ARM_1977__13_4_a4,
     author = {Nikolova, T. St. and Bajnov, Drumi Dimitrov},
     title = {{\CYRK}{\cyrr}{\cyra}{\cyre}{\cyrv}{\cyra}{\cyrya} {\cyrz}{\cyra}{\cyrd}{\cyra}{\cyrch}{\cyra} {\cyrs} {\cyrp}{\cyra}{\cyrr}{\cyra}{\cyrm}{\cyre}{\cyrt}{\cyrr}{\cyra}{\cyrm}{\cyri} {\cyrd}{\cyrl}{\cyrya} {\cyrd}{\cyri}{\cyrf}{\cyrf}{\cyre}{\cyrr}{\cyre}{\cyrn}{\cyrc}{\cyri}{\cyra}{\cyrl}{\cyrsftsn}{\cyrn}{\cyrery}{\cyrh} {\cyru}{\cyrr}{\cyra}{\cyrv}{\cyrn}{\cyre}{\cyrn}{\cyri}{\cyrishrt} {\cyrs}{\cyrv}{\cyre}{\cyrr}{\cyrh}{\cyrn}{\cyre}{\cyrishrt}{\cyrt}{\cyrr}{\cyra}{\cyrl}{\cyrsftsn}{\cyrn}{\cyro}{\cyrg}{\cyro} {\cyrt}{\cyri}{\cyrp}{\cyra}},
     journal = {Archivum mathematicum},
     pages = {201--206},
     publisher = {mathdoc},
     volume = {13},
     number = {4},
     year = {1977},
     mrnumber = {0466854},
     zbl = {0405.34032},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ARM_1977__13_4_a4/}
}