Topological degree and boundary value problems for nonlinear differential equations
1967 ◽
Vol 5
(7)
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pp. 571-588
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1996 ◽
Vol 26
(4)
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pp. 1499-1515
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2011 ◽
Vol 218
(8)
◽
pp. 4090-4118
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2004 ◽
Vol 290
(2)
◽
pp. 620-638
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