@misc{MP_2023_3_30_a25,
     title = {{\CYRP}{\cyro}{\cyrp}{\cyrr}{\cyra}{\cyrv}{\cyrk}{\cyra}},
     journal = {Matematicheskoe Prosveshchenie},
     pages = {247},
     year = {2023},
     volume = {Ser. 3, 30},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MP_2023_3_30_a25/}
}