Eigenfunction expansions associated with second-order differential equations for Hilbert space-valued functions
1971 ◽
Vol 7
(1)
◽
pp. 1-55
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1959 ◽
Vol 65
(3)
◽
pp. 151-155
1948 ◽
Vol 54
(5)
◽
pp. 485-488
1985 ◽
Vol 101
(3-4)
◽
pp. 237-252
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