@article{MMO_1982_45_a4,
     author = {A. S. Markus and V. I. Matsaev},
     title = {Comparison theorems for spectra of linear operators and spectral asymptotics},
     journal = {Trudy Moskovskogo matemati\v{c}eskogo ob\^{s}estva},
     pages = {133--181},
     publisher = {mathdoc},
     volume = {45},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MMO_1982_45_a4/}
}