@article{DE_1972_8_7_a26,
     author = {P. K. Senatorov},
     title = {Letter to the editors},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1332},
     year = {1972},
     volume = {8},
     number = {7},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1972_8_7_a26/}
}