@article{DAN_1957_117_6_a4,
     author = {K. M. Fishman and Yu. N. Valitskii},
     title = {The applicability of {Fredholm{\textquoteright}s} theory to certain linear topological spaces},
     journal = {Doklady Akademii Nauk},
     pages = {943--946},
     publisher = {mathdoc},
     volume = {117},
     number = {6},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_117_6_a4/}
}