DOCBOOK-APPS: Automatic copying of text between chapters

[dbook@centrum.cz]

Hello, 

do you now some docbook's construction, which provides automatic 
copying of text from one chapter to other?

Specially, i make in docbook course of c-language. I need to 
place exercises for students into end of every chapter and 
solutions with exercises again into appendix. Because exercises 
and solutions are large and will be often updated, i want to 
update it only in appendix. And into end of chapters i want only 
copy text of exercise from appendix and put there link to 
solution. Is it possibly?

My idea:

This is "main" file:
---------------------------------------------------------------
<!DOCTYPE book PUBLIC "-//OASIS//DTD Docbook XML V4.1.2//EN"
 "file:///d:\DocBook\DOCBOOK\docbookx.dtd"
  [
 <!ENTITY some_alias SYSTEM "file.xml">
 <!ENTITY some_alias2 SYSTEM "file2.xml">
...
 ]>
   
<book lang="cs">
...
<appendix>
<title>...
&some_alias;
&some_alias2;
&some_alias3;
...
</appendix>
...
---------------------------------------------------------------

And this is in 'file.xml':
---------------------------------------------------------------
<section>
<title>Exercises with solutions from chapter 1</title>

<exercise> bla bla bla bla bla bla bla bla bla bla </exercise>
<solution id="ex1"> ble ble ble ble ble ble ble ble ble ble 
</solution>
...
</section>
---------------------------------------------------------------


Every section with multiple exercises/solutions is equal to one 
chapter. 

Every section is placed to one XML file.

On the end of chapters i placed:

---------------------------------------------------------------
<exe-sol>
&some_alias;
</exe-sol>

<link linkend="ex1">Link</link> to solution
---------------------------------------------------------------

Here is structure of <exe-sol>:
---------------------------------------------------------------
<xsl:template match="exe-sol">
  <div class="exe-sol">
   <xsl:apply-templates select="section/exercise"/>
   </div>
</xsl:template>
---------------------------------------------------------------

Problem is, that it makes link to actual chapter, not to 
appendix/section 
(multiple "IDs" for constraint linkend:...).

Do you have some idea?

Thank you,
Petr Rajsky

--------------------
Centrum pro milovníky peněz http://finance.centrum.cz