> please do You know if the XSL document can define and handle global 
> variables ?

Yes (as you could discover by taking a copy of the XSLT spec and search
for "global").

Global variables are defined by xsl:variable just as for variables that
are local to a template body. The xsl:variable in the global case is at
the "top level2 ie a child of xsl:template.
Such variables may be used in all templates in the stylesheet (although
temnplates may not of course change the value of the variable.

David

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