Existence of multiple periodic solutions for a class of second-order delay differential equations
2009 ◽
Vol 10
(5)
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pp. 3285-3297
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2019 ◽
Vol 9
(3)
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pp. 298
2004 ◽
Vol 81
(6)
◽
pp. 707-717
2017 ◽
Vol 10
(04)
◽
pp. 1960-1970
2010 ◽
Vol 9
(6)
◽
pp. 1529-1542
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