I need to transform the following xml doc:

<a>
  <b/>
  <c/>
   myText
</a>

into this:

<a>
  <b/>
  <c/>
   differentText
</a>

So, i wrote this XSLT document

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output method="xml" version="1.0" omit-xml-declaration="no" />

  <xsl:template match="/a/text()">
    <a>
      <b/>
      <c/>
      differentText
    </a>
</xsl:template>
</xsl:stylesheet>

This way, i get the following result:

<?xml version="1.0" encoding="utf-8"?>
<a>
  <b /><c />
  differentText
</a>
<a>
  <b /><c />
  differentText
</a>
<a>
  <b /><c />
  differentText
</a>

The result appears repeated 3 times because 3 matches are being done.. Why? I could i fix it? Thanks