@article{MZM_1969_5_2_a11,
     author = {G. I. Bass},
     title = {The asymptotic behavior of the spectral function for elliptic operators in an~unbounded region},
     journal = {Matemati\v{c}eskie zametki},
     pages = {245--251},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1969_5_2_a11/}
}