[xsl] checking sequential element

["Ganesh Babu N" <nbabuganesh@xxxxxxxxx>]

Dear All,

I want to test the presence of <delim/> tag after </citau> in the
below example. If it is missing the XSL should raise an error.

<citref id="bib12">
 <citaug>
 <citau>
   <citsname>Ferri</citsname>
   <delim/>
   <citfnames>E</citfnames>
 </citau>
 <delim/>
 <cittext>(ed.).</cittext>
</citaug>

I have tried the following code but i am not getting the required result.

<xsl:template match="citref">
 <xsl:if test="citau/following-sibling::*[1]/self::delim">
  <xsl:message>citau does not followed by delim</xsl:message>
 </xsl:if>
</xsl:template>

Please help me in getting the desired result.

Regards,
Ganesh