A criterion for discreteness of the spectrum of a Sturm-Liouville equation with an operator coefficient (apropos the article by B. M. Levitan and G. A. Suvorchenkova)
1968 ◽
Vol 2
(2)
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pp. 153-157
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1976 ◽
Vol 10
(1)
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pp. 145-180
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1972 ◽
Vol 5
(4)
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pp. 322-323
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1968 ◽
Vol 5
(2)
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pp. 229-259
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Keyword(s):
1973 ◽
Vol 24
(3)
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pp. 241-250
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Keyword(s):
2012 ◽
Vol 36
(13)
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pp. 1685-1700
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Keyword(s):