The spectral properties of many‐electron atomic Hamiltonians and the method of configuration interaction. II. Compactness proof associated with an infinite system of linear equations for two‐electron atoms
1949 ◽
Vol 2
(4)
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pp. 428-451
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1977 ◽
Vol 82
(2)
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pp. 269-273
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2005 ◽
Vol 168
(1)
◽
pp. 636-650
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