Xslt- preceding-sibling within for-each

Question

So I have this xml code and two of the nodes have the same ID-value. How can I not display the same node if it has the same value as a preceding-sibling?

That is if A = 12, B = 10, C = !2. The Xslt file shouldn't display C as it has the same value as A.

here the XML

<Services>
    <ServiceBooking> 
        <ID>A</ID>               
        <ServiceID>12</ServiceID>        
    </ServiceBooking>
    <ServiceBooking>
        <ID>B</ID>            
        <ServiceID>10</ServiceID>        
    </ServiceBooking>
    <ServiceBooking>
        <ID>C</ID>        
        <ServiceID>12</ServiceID>        
    </ServiceBooking>
</services>

and the Xslt

<xsl:for-each select="Services/ServiceBooking[not(preceding-sibling::ServiceID)]">
    <tr>
        <td class="name"><xsl:value-of select="ID" /></td>
        <td><xsl:value-of select="ServiceID"/></td>
    </tr>
</xsl:for-each>

Can anyone of you guys help me with this?

mvh

Solution

<xsl:for-each select="Services/ServiceBooking[not(ServiceID = preceding-sibling::ServiceBooking/ServiceID)]"> should do but you should learn about Muenchian grouping in XSLT 1.0 or for-each-group in XSLT 2.0.