Some problems of the spectral theory of a second-order differential equation with a variable unbounded operator coefficient
1971 ◽
Vol 5
(1)
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pp. 9-18
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2004 ◽
Vol 2004
(12)
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pp. 997-1005
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1975 ◽
Vol 26
(4)
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pp. 436-439
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1994 ◽
Vol 15
(5-6)
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pp. 583-598
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1962 ◽
Vol 10
(3)
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pp. 454-468
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2010 ◽
Vol 216
(9)
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pp. 2718-2727
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1931 ◽
Vol 27
(4)
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pp. 546-552
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