> can XSLT remember the occurrence of an element?

XSLT is a declarative language, not a procedural one, so there is no notion
of time in its processing model. There is no "before" and "after", and
therefore no notion of memory.

> Any ideas how I could change the xsl to only include *one* 
> instance of a
> contract despite it is *two or more* times called? 

The problem of eliminating duplicates is generally known as "grouping" and
is covered in http://www.jenitennison.com/xslt/grouping

Michael Kay
http://www.saxonica.com/