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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">109</journal-id>
      <journal-id journal-id-type="index">urn:lsid:arphahub.com:pub:3dc5f44e-8666-58db-bc76-a455210e8891</journal-id>
      <journal-title-group>
        <journal-title xml:lang="en">JUCS - Journal of Universal Computer Science</journal-title>
        <abbrev-journal-title xml:lang="en">jucs</abbrev-journal-title>
      </journal-title-group>
      <issn pub-type="ppub">0948-695X</issn>
      <issn pub-type="epub">0948-6968</issn>
      <publisher>
        <publisher-name>Journal of Universal Computer Science</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.3217/jucs-019-06-0750</article-id>
      <article-id pub-id-type="publisher-id">23243</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Research Article</subject>
        </subj-group>
        <subj-group subj-group-type="scientific_subject">
          <subject>F.0 - GENERAL</subject>
          <subject>F.1.1 - Models of Computation</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>The Riesz Representation Operator on the Dual of C[0; 1] is Computable</article-title>
      </title-group>
      <contrib-group content-type="authors">
        <contrib contrib-type="author" corresp="yes">
          <name name-style="western">
            <surname>Jafarikhah</surname>
            <given-names>Tahereh</given-names>
          </name>
          <email xlink:type="simple">t.jafarikhah@modares.ac.ir</email>
          <xref ref-type="aff" rid="A1">1</xref>
        </contrib>
        <contrib contrib-type="author" corresp="no">
          <name name-style="western">
            <surname>Weihrauch</surname>
            <given-names>Klaus</given-names>
          </name>
        </contrib>
      </contrib-group>
      <aff id="A1">
        <label>1</label>
        <addr-line content-type="verbatim">University of Tarbiat Modares, Tehran, Iran</addr-line>
        <institution>University of Tarbiat Modares</institution>
        <addr-line content-type="city">Tehran</addr-line>
        <country>Iran</country>
      </aff>
      <author-notes>
        <fn fn-type="corresp">
          <p>Corresponding author: Tahereh Jafarikhah (<email xlink:type="simple">t.jafarikhah@modares.ac.ir</email>).</p>
        </fn>
        <fn fn-type="edited-by">
          <p>Academic editor: </p>
        </fn>
      </author-notes>
      <pub-date pub-type="collection">
        <year>2013</year>
      </pub-date>
      <pub-date pub-type="epub">
        <day>28</day>
        <month>03</month>
        <year>2013</year>
      </pub-date>
      <volume>19</volume>
      <issue>6</issue>
      <fpage>750</fpage>
      <lpage>770</lpage>
      <uri content-type="arpha" xlink:href="http://openbiodiv.net/07673789-901A-5AB4-9422-BEA815F9DF1F">07673789-901A-5AB4-9422-BEA815F9DF1F</uri>
      <uri content-type="zenodo_dep_id" xlink:href="https://zenodo.org/record/5505199">5505199</uri>
      <history>
        <date date-type="received">
          <day>25</day>
          <month>04</month>
          <year>2012</year>
        </date>
        <date date-type="accepted">
          <day>25</day>
          <month>03</month>
          <year>2012</year>
        </date>
      </history>
      <permissions>
        <copyright-statement>Tahereh Jafarikhah, Klaus Weihrauch</copyright-statement>
        <license license-type="creative-commons-attribution" xlink:href="" xlink:type="simple">
          <license-p>This article is freely available under the J.UCS Open Content License.</license-p>
        </license>
      </permissions>
      <abstract>
        <label>Abstract</label>
        <p>By the Riesz representation theorem, for every linear functional F : C[0; 1] → ℝ there is a function g : [0; 1] → ℝ of bounded variation such that  A computable version is proved in [Lu and Weihrauch(2007)]: a function g can be computed from F and its norm, and F can be computed from g and an upper bound of its total variation. In this article we present a much more transparent proof. We first give a new proof of the classical theorem from which we then can derive the computable version easily. As in [Lu and Weihrauch(2007)] we use the framework of TTE, the representation approach for computable analysis, which allows to define natural concepts of computability for the operators under consideration.</p>
      </abstract>
    </article-meta>
  </front>
</article>
