Periodic solutions of a discrete Hamiltonian system with a change of sign in the potential
2006 ◽
Vol 324
(2)
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pp. 1140-1151
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2013 ◽
Vol 394
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pp. 92-95
2020 ◽
Vol 43
(6)
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pp. 4393-4409
2013 ◽
Vol 219
(12)
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pp. 6548-6555
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