<article>
  <title>Test</title>

  <section>
    <title id="chapter-first">First</title>

    <para>Some text...</para>
  </section>

  <section>
    <title>Second</title>

    <para>Some text...</para>
  </section>

  <section>
    <title>Link elements</title>

      <section>
        <title>Internal links</title>

        <para>Element name: <code>link</code>.</para>       

        <para>Example:</para>

        <para>Please click <link linkend="chapter-first">here</link> to
        go to the Introduction chapter.</para>

        <para>Links without a correct target set, like <link
        linkend="incorrect-target">this</link>, should be highlighted but
        shouldn't take the reader to another place.</para>
      </section>

      <section>
        <title>External links</title>
        
        <para>Example:</para>

        <para>Please click <ulink
        url="http://www.google.com">here</ulink> </para>
      </section>
    </section>
</article>

<xsl:stylesheet version = '1.0' 
     xmlns:xsl='http://www.w3.org/1999/XSL/Transform'>

<xsl:template match="title"> 
 <h1 align="center">
  <xsl:value-of select="."/>
 </h1>
</xsl:template>

<xsl:template match="section">
 <xsl:apply-templates/> 
</xsl:template>

<xsl:template match="section/title">
 <H2>
  <xsl:value-of select="."/>
 </H2>
</xsl:template>

<xsl:template match="@*|node()">
 <xsl:copy>
  <xsl:apply-templates select="@*|node()"/>
 </xsl:copy>
</xsl:template>

<xsl:template match="para">
 <xsl:apply-templates select="@*|node()"/>
</xsl:template>

<xsl:template match="link">
 <u style="color:Yellow">
  <a href="#{@linkend}"> <xsl:value-of select="."/>
  </a>
 </u>
</xsl:template>

<xsl:template match="ulink">
 <u style="color:Green">
  <a>
   <xsl:attribute name="href">
   <xsl:value-of select="@url" />
   </xsl:attribute>
   <xsl:value-of select="." />
  </a>
 </u> 
</xsl:template>

</xsl:stylesheet>