Eigenva1ue Distribution of Invariant Linear Second Order Elliptic Differential Operators with Constant Coefficients
1991 ◽
Vol 42
(6)
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pp. 848-863
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1966 ◽
Vol 72
(3)
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pp. 538-542
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1976 ◽
Vol 29
(6)
◽
pp. 595-621
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2014 ◽
Vol 287
(16)
◽
pp. 1848-1885
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1967 ◽
Vol 43
(2)
◽
pp. 82-86
◽
1988 ◽
Vol 109
(1-2)
◽
pp. 127-144
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