about Id & IDREF

Hi all ! 
m an novice user of xml
I was tasked to work on XML database
I have created one DTD Wherein i am using bulletin as one of the ELEMENTS
I am describing this element in another DTD called Bulletin.dtd
The reson for creatig separe DTD for Bulletin is that I can use 1 'bulletin
doc" for 2/3 "product document"
i.e. Bulletin is a doc of assembly procedure ..and 2 /3 diff product can
have same bulletin 

E g. Product.dtd

<!ELEMENT Item ((partName | prodName) , Item* , productImage , description?
, CatalogID? , Bulletin?) > 
And Bulletin.dtd
<?xml version='1.0' encoding='UTF-8' ?> 
<!ENTITY % date "CDATA"> 
<!ELEMENT Bulletin (tilte , requisit? , note* , list+)> 
<!ATTLIST Bulletin UID ID #REQUIRED
update %date; #IMPLIED >
<!ELEMENT tilte (#PCDATA)> 
<!ELEMENT requisit (list+)> 
<!ELEMENT note (#PCDATA)> 
<!ELEMENT list (#PCDATA)> 
My question is how to link these two docments .with ID and IDREF[Kakade
Mangesh] ( i dont want to use Xlink or XSLT) 
TIA, 
Mangesh 


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