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@article{DAN_1964_159_4_a0, author = {M. Ya. Azbel'}, title = {On the spectrum of difference equations with periodic coefficients}, journal = {Doklady Akademii Nauk}, pages = {703--706}, publisher = {mathdoc}, volume = {159}, number = {4}, year = {1964}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1964_159_4_a0/} }
M. Ya. Azbel'. On the spectrum of difference equations with periodic coefficients. Doklady Akademii Nauk, Tome 159 (1964) no. 4, pp. 703-706. http://geodesic.mathdoc.fr/item/DAN_1964_159_4_a0/