@article{VMUMM_1982_5_a15,
     author = {M. A. Shubin},
     title = {Essentiality of the spectrum of pseudodifferential operators in the {Besicovitch} space $B^2(\mathbf{R}^n)$},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {56--59},
     publisher = {mathdoc},
     number = {5},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1982_5_a15/}
}