@article{DAN_1975_224_4_a8,
     author = {G. P. Chistyakov},
     title = {On a problem of {Dugue}},
     journal = {Doklady Akademii Nauk},
     pages = {775--778},
     publisher = {mathdoc},
     volume = {224},
     number = {4},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1975_224_4_a8/}
}