@article{IVM_1973_5_a13,
     author = {T. O. Shaposhnikova},
     title = {A~priori estimates of the error of the {Ritz} method in the eigenvalue problem of degenerate higher order elliptic operators},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {99--108},
     publisher = {mathdoc},
     number = {5},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1973_5_a13/}
}