A Fermi-type rule for contact embedded-eigenvalue perturbations
1954 ◽
Vol 11
(4)
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pp. 505-509
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1985 ◽
Vol 26
(7)
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pp. 1570-1575
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2015 ◽
pp. 1471-1475
2004 ◽
Vol 37
(27)
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pp. 6943-6954
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1993 ◽
Vol 18
(7-8)
◽
pp. 1149-1159
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