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               <dc:title>A note of the periodic orbits of a kind of Duffing equations</dc:title>
               <dc:creator>Llibre, Jaume</dc:creator>
               <dc:creator>Rodrigues, Ana</dc:creator>
               <dc:description>Agraïments: The second author was supported by FCT Grant BPD/36072/2007. Research of AR supported in part by Centro de Matemática da Universidade do Porto (CMUP) financed by FCT through the programmes POCTI and POSI, with Portuguese and European Community structural funds.</dc:description>
               <dc:description>We study the periodic orbits of the modified Duffing differential equation ¨y + ay - εy3 = εh(y, y˙), with a.</dc:description>
               <dc:date>2013</dc:date>
               <dc:type>Article</dc:type>
               <dc:relation>Ministerio de Ciencia e Innovación MTM2008-03437</dc:relation>
               <dc:relation>Agència de Gestió d'Ajuts Universitaris i de Recerca 2009/SGR-410</dc:relation>
               <dc:relation>Applied Mathematics and Computation ; Vol. 219 (2013), p. 8358-8365</dc:relation>
               <dc:rights>open access</dc:rights>
               <dc:rights>Aquest material està protegit per drets d'autor i/o drets afins. Podeu utilitzar aquest material en funció del que permet la legislació de drets d'autor i drets afins d'aplicació al vostre cas. Per a d'altres usos heu d'obtenir permís del(s) titular(s) de drets.</dc:rights>
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