On the number of solutions of some ordinary periodic boundary value problems by their geometrical properties
1991 ◽
Vol 160
(1)
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pp. 89-127
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2009 ◽
Vol 19
(1)
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pp. 80-104
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2016 ◽
Vol 5
(4)
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pp. 195-214
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2009 ◽
Vol 3
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pp. 501-509
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1997 ◽
Vol 28
(6)
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2014 ◽
Vol 34
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pp. 1225-1236
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