foreign keys in a xml-database

Hi folks,

does anybody know, whether there is a technique of defining foreign keys in a xml-database by xml or xsl??

I want to avoid redundancies and therefor to store often used elements in a seperate xml-file. The strukture of my main xml-file shall only contain references to the seperately saved elements and not the whole data each time. Is there any posibbility to do so???


Many thanks in advance,

Stefan Greim

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list