@article{VMUMM_1988_5_a9,
     author = {V. V. Dubrovskii and A. V. Nagornyi},
     title = {On an estimate for the difference of spectral functions of discrete operators in $L^2$},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {44--47},
     publisher = {mathdoc},
     number = {5},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1988_5_a9/}
}