<?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>0120-419X</journal-id>
<journal-title><![CDATA[Revista Integración]]></journal-title>
<abbrev-journal-title><![CDATA[Integración - UIS]]></abbrev-journal-title>
<issn>0120-419X</issn>
<publisher>
<publisher-name><![CDATA[Universidad Industrial de Santander]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-419X2019000200251</article-id>
<article-id pub-id-type="doi">10.18273/revint.v37n2-2019003</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[A survey of s-unital and locally unital rings]]></article-title>
<article-title xml:lang="es"><![CDATA[Una revisión de anillos s-unitarios y localmente unitarios]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Nystedt]]></surname>
<given-names><![CDATA[Patrik]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,University West Department of Engineering Science ]]></institution>
<addr-line><![CDATA[Trollháttan ]]></addr-line>
<country>Sweden</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>37</volume>
<numero>2</numero>
<fpage>251</fpage>
<lpage>260</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-419X2019000200251&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-419X2019000200251&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-419X2019000200251&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract We gather some classical results and examples that show strict inclusion between the families of unital rings, rings with enough idempotents, rings with sets of local units, locally unital rings, s-unital rings and idempotent rings. MSC2010: 1602, 16D99, 16S99, 16U99.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Recopilamos algunos resultados clásicos y ejemplos que muestran una inclusión estricta entre las familias de anillos unitarios, anillos con suficientes idempotentes, anillos con conjuntos de unidades locales, anillos localmente unitarios, anillos s-unitarios y anillos idempotentes.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Unital ring]]></kwd>
<kwd lng="en"><![CDATA[rings with enough idempotents]]></kwd>
<kwd lng="en"><![CDATA[rings with sets of local units]]></kwd>
<kwd lng="en"><![CDATA[locally unital ring]]></kwd>
<kwd lng="en"><![CDATA[s-unital ring]]></kwd>
<kwd lng="en"><![CDATA[idempotent ring]]></kwd>
<kwd lng="es"><![CDATA[Anillo unitario]]></kwd>
<kwd lng="es"><![CDATA[anillos con suficientes idempotentes]]></kwd>
<kwd lng="es"><![CDATA[anillos con conjuntos de unidades locales]]></kwd>
<kwd lng="es"><![CDATA[anillo localmente unitario]]></kwd>
<kwd lng="es"><![CDATA[anillo s-unitario]]></kwd>
<kwd lng="es"><![CDATA[anillo idempotente]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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