@article{DE_1984_20_3_a23,
     author = {V. A. Korobitsyn},
     title = {Transformations of two-layer difference operators},
     journal = {Differencialʹnye uravneni\^a},
     pages = {533--536},
     publisher = {mathdoc},
     volume = {20},
     number = {3},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1984_20_3_a23/}
}