Positive Periodic Solutions of Systems of Second Order Ordinary Differential Equations
2010 ◽
Vol 129
(1-2)
◽
pp. 166-181
◽
2004 ◽
Vol 25
(03)
◽
pp. 413-420
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2005 ◽
Vol 18
(11)
◽
pp. 1256-1264
◽
2006 ◽
Vol 73
(2)
◽
pp. 175-182
◽
2010 ◽
Vol 82
(3)
◽
pp. 437-445
◽
2018 ◽
Vol 15
(3)
◽
2021 ◽
Vol 57
◽
pp. 103200
2015 ◽
Vol 144
(1)
◽
pp. 1-10
◽