Perturbation results of second order linear differential equations with periodic coefficients
2007 ◽
Vol 22
(4)
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pp. 405-412
1973 ◽
Vol 6
(4)
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pp. 603-606
1986 ◽
Vol 17
(2)
◽
pp. 422-450
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1991 ◽
Vol 7
(4)
◽
pp. 354-359
◽
1968 ◽
Vol 79
(1)
◽
pp. 391-398
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Keyword(s):
Keyword(s):
1931 ◽
Vol 27
(4)
◽
pp. 546-552
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