DOCBOOK: Declaring entities in different files

[Horacio MG <homega@ciberia.es>]

I've been bumping my head against the book and the keyboard searching
for a suitable way to do the following:


	---------- book.sgml ----------

<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [
<!ENTITY chap.1 system "chap1/chap.1.sgml">
<!ENTITY chap.2 system "chap2/chap.2.sgml">
<!ENTITY chap.3 system "chap3/chap.3.sgml">

<book id="manual" lang="es">
<bookinfo>
...
<abstract>...</abstract>
</bookinfo>

&chap.1;
&chap.2;
&chap.3;

</book>
	---------- book.sgml ----------


        ---------- chap.1.sgml ----------

<chapter id="uno" lang="es">

<title>...</title>
<abstract>...</abstract>

</chapter>
        ---------- chap.1.sgml ----------

It is in these chap.x.sgml files that I want to declare other files
(reference pages), but as these "second level" files don't admit a
doctype declaration, how could I include the entities?

Now, the point of this is to have entities for "third level" files
declared in various "second level" files (chap.x.sgml) in an orderly
manner, and not just one big "first level" file (book.sgml).

This tree has some other problems, but I'll leave them for later.


Thank you,

-- 
Horacio					Anno MMDCCLIII A.U.C.
hacho@crosswinds.net			Valencia - ESPAŅA
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