@article{ARM_1990__26_2-3_a6, author = {Izobov, N. A. and Stepanovich, O. P.}, title = {O{\cyrb} {\cyri}{\cyrn}{\cyrv}{\cyra}{\cyrr}{\cyri}{\cyra}{\cyrn}{\cyrt}{\cyrn}{\cyro}{\cyrs}{\cyrt}{\cyri} {\cyrh}{\cyra}{\cyrr}{\cyra}{\cyrk}{\cyrt}{\cyre}{\cyrr}{\cyri}{\cyrs}{\cyrt}{\cyri}{\cyrch}{\cyre}{\cyrs}{\cyrk}{\cyri}{\cyrh} {\cyrp}{\cyro}{\cyrk}{\cyra}{\cyrz}{\cyra}{\cyrt}{\cyre}{\cyrl}{\cyre}{\cyrishrt} {\cyrl}{\cyri}{\cyrn}{\cyre}{\cyrishrt}{\cyrn}{\cyrery}{\cyrh} {\cyrs}{\cyri}{\cyrs}{\cyrt}{\cyre}{\cyrm} {\cyrp}{\cyrr}{\cyri} {\cyrerev}{\cyrk}{\cyrs}{\cyrp}{\cyro}{\cyrn}{\cyre}{\cyrn}{\cyrc}{\cyri}{\cyra}{\cyrl}{\cyrsftsn}{\cyrn}{\cyro} {\cyru}{\cyrb}{\cyrery}{\cyrv}{\cyra}{\cyryu}{\cyrshch}{\cyri}{\cyrh} {\cyrv}{\cyro}{\cyrz}{\cyrm}{\cyru}{\cyrshch}{\cyre}{\cyrn}{\cyri}{\cyrya}{\cyrh}}, journal = {Archivum mathematicum}, pages = {107,108}, publisher = {mathdoc}, volume = {26}, number = {2-3}, year = {1990}, mrnumber = {1188269}, zbl = {0729.34030}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/ARM_1990__26_2-3_a6/} }