<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0035-001X</journal-id>
<journal-title><![CDATA[Revista mexicana de física]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fis.]]></abbrev-journal-title>
<issn>0035-001X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0035-001X2019000600618</article-id>
<article-id pub-id-type="doi">10.31349/revmexfis.65.618</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[On fractional liénard-type systems]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Fleitas]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mendez-Bermúdez]]></surname>
<given-names><![CDATA[J.A.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Napoles Valdes]]></surname>
<given-names><![CDATA[J.E.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Sigarreta Almira]]></surname>
<given-names><![CDATA[J.M.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autonoma de Guerrero  ]]></institution>
<addr-line><![CDATA[Acapulco de Juarez Guerrero]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Carlos III de Madrid Departamento de Matemáticas ]]></institution>
<addr-line><![CDATA[Leganés Madrid]]></addr-line>
<country>Spain</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Benemerita Universidad Autonoma de Puebla Instituto de Física ]]></institution>
<addr-line><![CDATA[ Puebla]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Universidad Nacional del Nordeste Facultad de Ciencias Exactas y Naturales y Agrimensura ]]></institution>
<addr-line><![CDATA[Corrientes Capital ]]></addr-line>
<country>Argentina</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2019</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2019</year>
</pub-date>
<volume>65</volume>
<numero>6</numero>
<fpage>618</fpage>
<lpage>625</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2019000600618&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2019000600618&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2019000600618&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract In this work, we present numerical results of classical Lienard-type systems in a very general context, since we consider several types of derivatives (integer order and fractional order, global and local). Additionally, we made theoretical-methodological observations.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen En este trabajo, presentamos resultados numericos de sistemas tipo Lienard en un contexto muy general, puesto que consideramos varios tipos de derivadas (de orden entero y fraccionario, globales y locales). Adicionalmente, hacemos observaciones teóricas y metodológicas.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Lienard-type systems]]></kwd>
<kwd lng="en"><![CDATA[fractional derivatives]]></kwd>
<kwd lng="en"><![CDATA[numerical solutions]]></kwd>
<kwd lng="es"><![CDATA[Sistemas tipo Lienard]]></kwd>
<kwd lng="es"><![CDATA[derivadas fraccionarias]]></kwd>
<kwd lng="es"><![CDATA[soluciones numericas]]></kwd>
<kwd lng="en"><![CDATA[05.45.-a]]></kwd>
<kwd lng="en"><![CDATA[68.35.Ct]]></kwd>
<kwd lng="en"><![CDATA[68.65.-k]]></kwd>
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