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@article{DE_1970_6_5_a7, author = {G. V. Zhdanova}, title = {The asymptotics of the eigenvalues of a selfadjoint second order singular operator}, journal = {Differencialʹnye uravneni\^a}, pages = {838--851}, publisher = {mathdoc}, volume = {6}, number = {5}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1970_6_5_a7/} }
G. V. Zhdanova. The asymptotics of the eigenvalues of a selfadjoint second order singular operator. Differencialʹnye uravneniâ, Tome 6 (1970) no. 5, pp. 838-851. http://geodesic.mathdoc.fr/item/DE_1970_6_5_a7/