@article{ZNSL_1972_30_a20,
     author = {N. A. Shirokov},
     title = {{\CYRO}{\cyrb}{\cyro}{\cyrb}{\cyrshch}{\cyre}{\cyrn}{\cyri}{\cyre} {\cyrt}{\cyre}{\cyro}{\cyrr}{\cyre}{\cyrm}{\cyrery} {{\CYRL}{\cyri}{\cyrt}{\cyrt}{\cyrl}{\cyrv}{\cyru}{\cyrd}{\cyra}{\textendash}{\CYRP}{\cyrerev}{\cyrl}{\cyri}}},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {179--180},
     year = {1972},
     volume = {30},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1972_30_a20/}
}