@article{DAN_1993_333_3_a4,
     author = {A. K. Gushchin and V. P. Mikhailov},
     title = {The {Fredholmness} of a class of nonlocal problems for a},
     journal = {Doklady Akademii Nauk},
     pages = {290--292},
     publisher = {mathdoc},
     volume = {333},
     number = {3},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1993_333_3_a4/}
}