XML-QL (DAG queries, document binding,Construct structure)

Dear all,
	If you are familiar with XML-QL, maybe you can help me on that : 
 
	*I want to know if it's possible to refer in the construct clause
	to subelement of an element which I binded in the where clause.
	For example :

	Where <Book> </Book> ELEMENT_AS $b in "abc.xml"
	Construct <Result> $b\Author </Result>
		
	In this query I ment to retrieve from the xml file
	all the authors names. So is it possible ?
	(without demading in the where clause the author should be
	under book, without using regular expressions or 
	tag variables)

	*Another thing is how XML-QL deals with IDREFs in a query
	 how it's proccess and what the semantic of a DAG
	 query in XML-QL. (not the one like you'd mentioned at 
	 the article, which presents how to join by values,
	 I need to know how you treat join of reference)
 	
	*If I have a query with Construct clause only
	 where & how do I bind it to or on a given document? 

         Thank you in advance.
  x~~~x
 &&- -&&
 && i &&
   \v/
  /   \
  \\ //  Goodbye , Frieda Shachar
  --------------------------------
  Email:fridas@cs.huji.ac.il