Namespace of the layout ruleset

The XML namespace of the layout ruleset is urn:speedata.de:2009/publisher/en. The additional XPath functions are in the namespace urn:speedata:2009/publisher/functions/en. A layout ruleset should therefore always have this frame:

<Layout xmlns="urn:speedata.de:2009/publisher/en"
        xmlns:sd="urn:speedata:2009/publisher/functions/en">
 ...
</Layout>

Then you can call speedata’s own functions with the prefix sd:, for example: sd:current-page() to determine the current page number.