<?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>S0035-001X2003000300002</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Quintessence-like dark matter in spiral galaxies]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Siddhartha Guzmán]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Matos]]></surname>
<given-names><![CDATA[Tonatiuh]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Núñez]]></surname>
<given-names><![CDATA[Darío]]></given-names>
</name>
<xref ref-type="aff" rid="A03"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ramírez]]></surname>
<given-names><![CDATA[Erandy]]></given-names>
</name>
<xref ref-type="aff" rid="A03"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Max Planck Institute for Gravitational Physics (Albert Einstein Institute)  ]]></institution>
<addr-line><![CDATA[Golm Brandeburgo]]></addr-line>
<country>Alemania</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Instituto Politécnico Nacional Centro de Investigación y de Estudios Avanzados Departamento de Física]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<aff id="A03">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Ciencias Nucleares ]]></institution>
<addr-line><![CDATA[México Distrito Federal]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2003</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2003</year>
</pub-date>
<volume>49</volume>
<numero>3</numero>
<fpage>203</fpage>
<lpage>206</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2003000300002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2003000300002&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2003000300002&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Through the geodesic analysis of a static and axially symmetric space time, we present conditions on the state equation of an isotropic perfect fluid p = &#969;d, when it is considered as the dark matter in spiral galaxies. The main conclusion is that it can be an exotic fluid (-1 < &#969; < -1/3) as it is found for Quintessence at cosmological scale.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Por medio de un análisis de las geodésicas en un espacio axisimétrico y estático, obtenemos condiciones sobre la ecuación de estado para un fluido perfecto isotrópo, p = &#969;d, cuando éste es considerado como la materia obscura en las galaxias espirales. La conclusión principal es que dicho fluido puede ser exótico, es decir, con - 1 < o < - &#8531;, como se obtiene a escalas cosmológicas dentro del modelo de Quintaesencia.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Quintessence]]></kwd>
<kwd lng="en"><![CDATA[perfect fluid]]></kwd>
<kwd lng="es"><![CDATA[Quintaesencia]]></kwd>
<kwd lng="es"><![CDATA[fluido perfecto]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="justify"><font face="verdana" size="4">Investigaci&oacute;n</font></p>     <p align="justify">&nbsp;</p>  	    <p align="center"><font face="verdana" size="4"><b>Quintessence&#45;like dark matter in spiral galaxies</b></font></p>     <p align="center">&nbsp;</p>       	     <p align="center"><font face="verdana" size="2"><b>F. Siddhartha Guzm&aacute;n<sup>1</sup>, Tonatiuh Matos<sup>2</sup>, Dar&iacute;o N&uacute;&ntilde;ez<sup>3</sup> and Erandy Ram&iacute;rez<sup>3</sup></b></font></p>  	     <p align="center">&nbsp;</p>                 <p align="justify"><font face="verdana" size="2"><sup><i>1</i></sup> <i>Max Planck Institut f&uuml;r Gravitationsphysik, Am M&uuml;hlenberg 1, D&#45;14476 Golm, Germany.</i></font></p>                 <p align="justify"><font face="verdana" size="2"><sup><i>2</i></sup> <i>Departamento de F&iacute;sica, Centro de Investigaci&oacute;n y de Estudios Avanzados del IPN, Apartado Postal 14&#45;740, 07000 M&eacute;xico D.F., M&Eacute;XICO.</i></font></p>             <p align="justify"><font face="verdana" size="2"><sup><i>3</i></sup> <i>Instituto de Ciencias Nucleares, Universidad Nacional Aut&oacute;noma de M&eacute;xico, Apartado Postal 70&#45;543, 04510 M&eacute;xico D.F., M&Eacute;XICO.</i></font></p>     <p align="justify">&nbsp;</p>      ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">Recibido el 4 de marzo de 2002.     <br> Aceptado el 26 de septiembre de 2002.</font></p>     <p align="justify">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>      <p align="justify"><font face="verdana" size="2">Through the geodesic analysis of a static and axially symmetric space time, we present conditions on the state equation of an isotropic perfect fluid <i>p = &#969;d,</i> when it is considered as the dark matter in spiral galaxies. The main conclusion is that it can be an exotic fluid (&#45;1 &lt; &#969; &lt; &#45;1/3) as it is found for Quintessence at cosmological scale.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> Quintessence; perfect fluid.</font></p>     <p align="justify">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>      <p align="justify"><font face="verdana" size="2">Por medio de un an&aacute;lisis de las geod&eacute;sicas en un espacio axisim&eacute;trico y est&aacute;tico, obtenemos condiciones sobre la ecuaci&oacute;n de estado para un fluido perfecto isotr&oacute;po, <i>p = &#969;d</i>, cuando &eacute;ste es considerado como la materia obscura en las galaxias espirales. La conclusi&oacute;n principal es que dicho fluido puede ser ex&oacute;tico, es decir, con &#45; 1 &lt; o &lt; &#45; &#8531;, como se obtiene a escalas cosmol&oacute;gicas dentro del modelo de Quintaesencia.</font></p>      <p align="justify"><font face="verdana" size="2"><b>Palabras clave:</b> Quintaesencia; fluido perfecto.</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">PACS: 95.35.+d, 95.35.G</font></p>     <p align="justify">&nbsp;</p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmf/v49n3/v49n3a2.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>     <p align="justify">&nbsp;</p>       <p align="justify"><font face="verdana" size="2"><b>Acknowledgments</b> This work is also partly supported by CONACYT M&eacute;xico, 94890 (Guzm&aacute;n) and by the DGAPA&#45;UNAM IN122002 and CONACYT grants (N&uacute;&ntilde;ez).</font></p>     <p align="justify">&nbsp;</p>      <p align="justify"><font face="verdana" size="2"><b>References</b></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">1. S. Perlmutter <i>et al., Ap. J.</i> 517 (1999) 565;    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294569&pid=S0035-001X200300030000200001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --> A.G. Riess <i>et al., Astron. J.</i> 116 (1998) 1009.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294570&pid=S0035-001X200300030000200002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">2. T. Matos, F.S. Guzm&aacute;n, and L.A. Ure&ntilde;a, <i>Class. Quant. Grav.</i> 17 (2000) 1707.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294572&pid=S0035-001X200300030000200003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">3. R.R. Caldwell, Rahul Dave, and P.J. Steinhardt, <i>Phys. Rev. Lett.</i> 80 (1988) 1582;    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294574&pid=S0035-001X200300030000200004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --> Ivaylo Zlatev, Limin Wang and P.J. Steinhardt, <i>Phys. Rev. Lett.</i> 82 (1988) 896.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294575&pid=S0035-001X200300030000200005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">4. V.C. Rubin, N. Thonnard, W.K. Ford and M.S. Roberts, <i>Ap. J.</i> 81 (1997) 719.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294577&pid=S0035-001X200300030000200006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">5. P.D. Mannheim, <i>Ap. J.</i> 479 (1997) 659.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294579&pid=S0035-001X200300030000200007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">6. Massimo Persic, Paolo Salucci and Fulvio Stel, <i>MNRAS</i> 281 (1996) 27.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294581&pid=S0035-001X200300030000200008&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">7. P.J.E. Peebles, <i>Principles</i> <i>of</i> <i>Physical Cosmology</i> (Princeton University Press, Princeton, 1993).    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294583&pid=S0035-001X200300030000200009&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">8. F. Siddhartha Guzm&aacute;n and T. Matos, <i>Class. Quant. Grav.</i> 17 (2000) L9&#45;L16;    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294585&pid=S0035-001X200300030000200010&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --> F.S. Guzm&aacute;n, T. Matos, and H. Villegas. Preprint astro&#45;ph/9811143.</font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">9. T. Matos, D. N&uacute;&ntilde;ez, F.S. Guzm&aacute;n, and E. Ram&iacute;rez, <i>Gen. Rel. and Grav.</i> 34 (2002) 283.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294587&pid=S0035-001X200300030000200011&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <p align="justify"><font face="verdana" size="2">10. M. Alcubierre <i>et al.,</i> gr&#45;qc/0110102.</font></p>      <p align="justify"><font face="verdana" size="2">11. E. Ram&iacute;rez, M. in Sc. thesis, UNAM&#45;M&eacute;xico (2001).</font></p>      <p align="justify"><font face="verdana" size="2">12. F.S. Guzm&aacute;n, T. Matos, D. N&uacute;&ntilde;ez, and E. Ram&iacute;rez (in preparation).</font></p>      ]]></body>
<body><![CDATA[<!-- ref --><p align="justify"><font face="verdana" size="2">13. S. Chandrasekhar, <i>Mathematical theory</i> <i>of</i> <i>black holes</i> (Oxford Science Publications 1983).    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294592&pid=S0035-001X200300030000200012&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      <!-- ref --><p align="justify"><font face="verdana" size="2">14. T. Matos, D. N&uacute;&ntilde;ez, and H. Quevedo <i>Phys. Rev D</i> 51 (1995) R310.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8294594&pid=S0035-001X200300030000200013&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p>      ]]></body><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Perlmutter]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Ap. J.]]></source>
<year>1999</year>
<volume>517</volume>
<page-range>565</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Riess]]></surname>
<given-names><![CDATA[A.G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Astron. J.]]></source>
<year>1998</year>
<volume>116</volume>
<page-range>1009</page-range></nlm-citation>
</ref>
<ref id="B3">
<label>2</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Matos]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Guzmán]]></surname>
<given-names><![CDATA[F.S.]]></given-names>
</name>
<name>
<surname><![CDATA[Ureña]]></surname>
<given-names><![CDATA[L.A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Class. Quant. Grav.]]></source>
<year>2000</year>
<volume>17</volume>
<page-range>1707</page-range></nlm-citation>
</ref>
<ref id="B4">
<label>3</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Caldwell]]></surname>
<given-names><![CDATA[R.R.]]></given-names>
</name>
<name>
<surname><![CDATA[Dave]]></surname>
<given-names><![CDATA[Rahul]]></given-names>
</name>
<name>
<surname><![CDATA[Steinhardt]]></surname>
<given-names><![CDATA[P.J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Phys. Rev. Lett.]]></source>
<year>1988</year>
<volume>80</volume>
<page-range>1582</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zlatev]]></surname>
<given-names><![CDATA[Ivaylo]]></given-names>
</name>
<name>
<surname><![CDATA[Wang]]></surname>
<given-names><![CDATA[Limin]]></given-names>
</name>
<name>
<surname><![CDATA[Steinhardt]]></surname>
<given-names><![CDATA[P.J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Phys. Rev. Lett.]]></source>
<year>1988</year>
<volume>82</volume>
<page-range>896</page-range></nlm-citation>
</ref>
<ref id="B6">
<label>4</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rubin]]></surname>
<given-names><![CDATA[V.C.]]></given-names>
</name>
<name>
<surname><![CDATA[Thonnard]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
<name>
<surname><![CDATA[Ford]]></surname>
<given-names><![CDATA[W.K.]]></given-names>
</name>
<name>
<surname><![CDATA[Roberts]]></surname>
<given-names><![CDATA[M.S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Ap. J.]]></source>
<year>1997</year>
<volume>81</volume>
<page-range>719</page-range></nlm-citation>
</ref>
<ref id="B7">
<label>5</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mannheim]]></surname>
<given-names><![CDATA[P.D.]]></given-names>
</name>
</person-group>
<source><![CDATA[Ap. J.]]></source>
<year>1997</year>
<volume>479</volume>
<page-range>659</page-range></nlm-citation>
</ref>
<ref id="B8">
<label>6</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Persic]]></surname>
<given-names><![CDATA[Massimo]]></given-names>
</name>
<name>
<surname><![CDATA[Salucci]]></surname>
<given-names><![CDATA[Paolo]]></given-names>
</name>
<name>
<surname><![CDATA[Stel]]></surname>
<given-names><![CDATA[Fulvio]]></given-names>
</name>
</person-group>
<source><![CDATA[MNRAS]]></source>
<year>1996</year>
<volume>281</volume>
<page-range>27</page-range></nlm-citation>
</ref>
<ref id="B9">
<label>7</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Peebles]]></surname>
<given-names><![CDATA[P.J.E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Principles of Physical Cosmology]]></source>
<year>1993</year>
<publisher-loc><![CDATA[Princeton ]]></publisher-loc>
<publisher-name><![CDATA[Princeton University Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B10">
<label>8</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Siddhartha Guzmán]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Matos]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
</person-group>
<source><![CDATA[Class. Quant. Grav.]]></source>
<year>2000</year>
<volume>17</volume>
<page-range>L9-L16</page-range></nlm-citation>
</ref>
<ref id="B11">
<label>9</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Matos]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Núñez]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Guzmán]]></surname>
<given-names><![CDATA[F.S.]]></given-names>
</name>
<name>
<surname><![CDATA[Ramírez]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Gen. Rel. and Grav.]]></source>
<year>2002</year>
<volume>34</volume>
<page-range>283</page-range></nlm-citation>
</ref>
<ref id="B12">
<label>13</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chandrasekhar]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<source><![CDATA[Mathematical theory of black holes]]></source>
<year>1983</year>
<publisher-name><![CDATA[Oxford Science Publications]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B13">
<label>14</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Matos]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Núñez]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Quevedo]]></surname>
<given-names><![CDATA[H.]]></given-names>
</name>
</person-group>
<source><![CDATA[Phys. Rev D]]></source>
<year>1995</year>
<volume>51</volume>
<page-range>R310</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
