@article{DE_1998_34_3_a12,
     author = {S. R. Umarov},
     title = {Nonlocal boundary value problems for pseudodifferential and operator-differential {equations.~II}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {375--382},
     publisher = {mathdoc},
     volume = {34},
     number = {3},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1998_34_3_a12/}
}