@article{DE_1976_12_5_a3,
     author = {A. G. Kamenskii},
     title = {Boundary value problems for equations with formally symmetric differential-difference operators},
     journal = {Differencialʹnye uravneni\^a},
     pages = {815--824},
     publisher = {mathdoc},
     volume = {12},
     number = {5},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1976_12_5_a3/}
}