<?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>1409-2433</journal-id>
<journal-title><![CDATA[Revista de Matemática Teoría y Aplicaciones]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. Mat]]></abbrev-journal-title>
<issn>1409-2433</issn>
<publisher>
<publisher-name><![CDATA[Centro de Investigaciones en Matemática Pura y Aplicada (CIMPA) y Escuela de Matemática, San José, Costa Rica.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1409-24332016000100277</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Ordering catacondensed hexagonal systems with respect to VDB topological indices]]></article-title>
<article-title xml:lang="es"><![CDATA[Ordenación de los sistemas hexagonales catacondensados con respecto a los índices topológicos VDB]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rada]]></surname>
<given-names><![CDATA[Juan]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad de Antioquia  ]]></institution>
<addr-line><![CDATA[ Medellín]]></addr-line>
<country>CO</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2016</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2016</year>
</pub-date>
<volume>23</volume>
<numero>1</numero>
<fpage>277</fpage>
<lpage>289</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1409-24332016000100277&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1409-24332016000100277&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1409-24332016000100277&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[AbstractIn this paper we give a complete description of the ordering relations in the set of catacondensed hexagonal systems, with respect to a vertexdegree-based topological index. As a consequence, extremal values of vertex-degree-based topological indices in special subsets of the set of catacondensed hexagonal systems are computed.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[ResumenEn este artículo presentamos una descripción completa de la relación de orden en el conjunto de sistemas hexagonales catacondensados, con respecto a un índice topológico basado en los grados de los vértices. Como consecuencia, se determinan los valores extremos de un índice topológico basados en los grados de los vértices en subconjuntos especiales del conjunto de sistemas hexagonales catacondensados.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[VDB topological indices]]></kwd>
<kwd lng="en"><![CDATA[catacondensed hexagonal systems]]></kwd>
<kwd lng="en"><![CDATA[ordering]]></kwd>
<kwd lng="en"><![CDATA[extremal values]]></kwd>
<kwd lng="es"><![CDATA[índices topológicos VDB]]></kwd>
<kwd lng="es"><![CDATA[sistemas hexagonales catacondensados]]></kwd>
<kwd lng="es"><![CDATA[orden]]></kwd>
<kwd lng="es"><![CDATA[valores extremos]]></kwd>
</kwd-group>
</article-meta>
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