I'm working in DocBook 5.0, creating a writing/editing/production environment. I validate my XML against the RNG schema version of DB5. To make my environment easier to use, I like to break up my books into multiple files, using xinclude to pull the chapters of the book into the book file. Works great in my XSLT. I like to use system entities to make it easier for my non-tech writers/editors to use some special characters. I set up an entities file with easy-to-use names for some common special characters (ex: &emDash; for —).I thought I read somewhere that you cannot use both entities and xinclude in the same XML file. I just tried it, though and it validates and transforms OK. Is this ok? Is there a problem here I'm not seeing? Here's how I declare all my stuff at the top of the book file:\[code\]<?xml version="1.0" encoding="UTF-8"?><?oxygen RNGSchema="http://www.oasis-open.org/docbook/xml/5.0/rng/docbookxi.rng" type="xml"?><!DOCTYPE book [<!ENTITY % entities SYSTEM "utilities/entities/entities.ent">%entities;]><book xmlns="http://docbook.org/ns/docbook" xmlns:xi="http://www.w3.org/2001/XInclude" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlnspf="http://www.idpf.org/2007/opf" version="5.0" xml:id="book">\[/code\]Thanks for any help!