@article{RM_1961_16_5_a10,
     author = {L. Ya. Makarova},
     title = {Investigation of domains of class~$\Sigma$},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     publisher = {mathdoc},
     volume = {16},
     number = {5},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/RM_1961_16_5_a10/}
}