@article{MZM_1989_46_4_a12,
     author = {A. V. Shkred},
     title = {Linearization of spectral problems with the parameter in their boundary conditions and the properties of the {M.\,V.~Keldysh} derived chains},
     journal = {Matemati\v{c}eskie zametki},
     pages = {99--109},
     publisher = {mathdoc},
     volume = {46},
     number = {4},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1989_46_4_a12/}
}