Necessary and sufficient conditions for the Riesz basis property of the eigen- and associated functions of high-order differential operators on an interval
1997 ◽
Vol 34
(01)
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pp. 192-207
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1991 ◽
Vol 434
(1892)
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pp. 643-656
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1983 ◽
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pp. 89-198
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1998 ◽
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pp. 47-60
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1989 ◽
Vol 41
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pp. 180-183
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2014 ◽
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pp. 1-12
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1998 ◽
Vol 21
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