Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MS_1953__74_2_a1, author = {{\CYRA}.{\CYRA}. {\CYRL}{\cyrya}{\cyrp}{\cyru}{\cyrn}{\cyro}{\cyrv}}, title = {{\CYRO} {\cyrk}{\cyrl}{\cyra}{\cyrs}{\cyrs}{\cyri}{\cyrf}{\cyri}{\cyrk}{\cyra}{\cyrc}{\cyri}{\cyri} $R$-{\cyrm}{\cyrn}{\cyro}{\cyrzh}{\cyre}{\cyrs}{\cyrt}{\cyrv}}, journal = {Matemati\v{c}eskij sbornik}, pages = {255--262}, publisher = {mathdoc}, volume = {74}, number = {2}, year = {1953}, zbl = {0050.05503}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MS_1953__74_2_a1/} }
А.А. Ляпунов. О классификации $R$-множеств. Matematičeskij sbornik, Tome 74 (1953) no. 2, pp. 255-262. http://geodesic.mathdoc.fr/item/MS_1953__74_2_a1/